Heres Josh Mankiewicz with the evil to come. It was hard to look away when peggy was in the picture. Her beauty was captivating. She was also smart, ambitious, and she loved that little girl. Peggys image survives in homemade movies from the days when she was relishing motherhood, blissfully unaware of the evil to come. I was always there for my mother. Always. Suzanne was that little girl and says her mom peggy was everything a mother should be. As a child, i ice skated. My mother would sit there all bundled up shivering. They grew up about 45 minutes north of new york city. We were able to go away to camp when we were little. My parents traveled. Reporter at first, peggy did what many women did in the 1960s. She stayed at home while her husband rob headed off to work. But peggy was drawn to something bigger than her suburban sanctuary. When suzanne was young, her mom was back in school earning her mba. She was probably one of the few women in the graduating class. Reporter and then went into a mans business . And went into a mans business and worked very hard. Much i can look the fictional character in the series madman, she broke the Glass Ceiling at xerox. They didnt have too many female managers, and peggy rose very quickly because she was very intelligent. Reporter and always welldressed. Peggy wore a lot of black. She loved to dress and wear the latest fashions. Reporter unlike her fashionable mom, suzanne was a blue jeans and tshirt kind of girl. Suzanne how do you explain suzanne . Shes quirky, athletic, outgoing. This is one of suzannes best friends. Shes spontaneous. Shes talkative. She also likes to be close to home. Reporter after college, she came back to Rockland County and went to work at xerox herself. One night in a bar, suzanne fell for actually, fell over a 17yearold race car driver named bobby. She actually stepped on me. We were fooling around and i somehow wound up slipping on the floor. She picked me up and we saw each other and started talking. Reporter 13 years later, suzanne and bobby, who was by then a welder and steamfitter, were married. Peggy was okay about it. Its not unreasonable to believe that maybe she was kind of hoping that her daughter would marry a guy who wore a suit to work . I think so. Yeah, i think she was hoping for a harvard soninlaw but she got a soninlaw that went to the school of hard knocks, you know. Reporter bobby made a good soninlaw. He was always there for peggy, especially after her husband died in 2003. By then, peggy was retired but never slowed down, traveling the world and treasuring her family. Her son jim was now a psychologist living in florida with his wife diana and their two children. I get the sense that jim was not as close to your parents as you were. I would agree to that. Reporter and why would that be . Maybe because of the distance that he was so far away. He did call, he did speak to them. But my brother is my brother. He kind of lived in his own world. Reporter but suzanne and her mom were very much in the same world. How often did you see your mother . Reporter almost every day suzanne would often drop in on her mom and when she wasnt visiting, she would be gone. Reporter in the afternoon, the evening, make sure she was home. Reporter it was almost like you were the parent and she was the kid. You were checking up on her . Oh, absolutely. Reporter life was good for this family until one morning in january of 2014. Suzanne went to check on her mother. Oh, my god oh, my god i need an ambulance right away. Reporter and everything changed. When we come back, the heartbreaking discovery that sets a mystery in motion. I was screaming. Suzanne is in the driveway and looking rather frazzled. The first thought was, oh, my god, she tripped and hit her head. No way did she fall down the stairs. Saturday, january 25th, 2014, started off cold and snowing. Susanne says her day started off as it nearly always did, calling her mother peggy. Called the cell. She didnt answer. I called the house. She didnt answer. I said, all right. Maybe shes in the bathroom or she went out into the garage for something. Reporter susanne, who lives in a suburb of new york city, called diana, her sisterinlaw in florida. And i said, have you spoken with mommy this morning . She said, you know, i called her at 7 30 and i havent heard back from her. Reporter now worried, susanne got in her car and drove to peggys house. As im driving, im calling the house, the cell, the house, the cell. No answer. And now im getting panicky. I pull into her driveway, and i saw the roof of her car through the garage door. And i said, oh, this is not going to be good. Reporter she was right. Susanne says she found peggy crumpled at the bottom of the stairs with a knife in her chest. And the first thought was, oh, my god. She tripped on the cat and fell and stuck herself. Reporter then she says she saw the blood. And i said, oh, my god, she must have hit her head when she fell. Reporter and then susanne did something that would later raise a number of questions. I pulled the knife. I was gonna do cpr. Reporter you pulled the knife out of her . Yeah. If your mother was laying there with something sticking out of her that was hurting her, what would you do . Youd want to make that hurt go away. Reporter could you tell whether she was dead or alive . When i touched her neck and she was kind of cold. Reporter susanne ran out of the house and called 911. Oh, my god oh, my god oh, my god. Rockland 911. What is the address of your emergency . I was screaming. Im sure the neighbors that were around heard. I need an ambulance right away maam calm down. Whats going on there . I think my mother fell down the stairs with a knife in her hand and stabbed herself. Reporter susanne was right about one thing. Peggy nadell was dead. Her next call was to her brother jim in florida. I called my brothers house. He didnt answer. I called diana on her cell, and i said, mommys gone. And she started screaming at the other end of the phone. What do you mean mommys gone . I said, shes gone. She died. Something happened. She died. Reporter soon Clarkstown Police detectives stephen colehatchard and earl lorence were on the scene. They noticed that susanne looked a wreck, standing in front of the house in the snow. Susanne is in the driveway, at the foot of the driveway, kind of pacing, looking rather frazzled. Reporter she told detectives what she told the 911 operators, that peggy tripped over the cat. Her mother must have tumbled down the stairs and stabbed herself with the knife. Reporter while detective colehatchard stayed outside with susanne, detective lorence went inside the house. This is police video of the scene taken that morning. Lorence knew right away, this was no accident. No way did she fall down the stairs and trip over a cat. Reporter detective lorence saw peggy had been strangled, then stabbed. And it also looked as if shed been beaten with a statue head found under her body and a gold metal ball near her hand. The crime scene itself was very concentrated. Everything was at the bottom of the stairs and in the bedroom upstairs. Reporter Something Else caught the detectives attention two chairs were pulled out at the kitchen table, as if peggy had been sitting and talking with someone. Peggys computer, wallet and jewelry were missing. A jewelry box lay near a chair in the living room, empty. But to earl lorence, the burglary looked phony. Staged. The bedroom drawers, they were neatly pulled out and neatly placed on the floor in front of the dresser. At normal burglary scenes stuff is everywhere. Reporter people go through it like a tornado. Correct. Reporter and this wasnt a breakandenter job. Police could tell that when they looked at the fresh snow outside the house. There was one set of footprints, and that was the responding officer checking the perimeter of the home. Reporter so nothing suggesting that somebody had walked around, cased the place . Not a thing. Reporter the front door hadnt been jimmied or broken in. There was a key in the deadbolt in the front door thats required to open the door from the inside. And that was in the lock. Reporter meaning peggy had unlocked it from inside . Correct. Reporter that afternoon detectives brought susanne and her husband bobby to the Police Station and started asking questions. You called your mother from the car . Yeah. Okay. Reporter susanne told them contractors had been doing work on peggys bathroom, and that peggy also had landscapers and a cleaning Woman Working for her. Im guessing you guys spent some significant time and effort running down all the people who had worked on the house . Absolutely. Reporter any of that go anywhere . Dozens of people, not a thing. Reporter who would want to kill peggy nadell, and why . Assistant District AttorneyRichard Moran thought he had an answer for that second question. Financially, she was in pretty good shape. Very good shape. Reporter peggy and her husband had built quite a large nest egg. All in all, the estate ended up being worth about 4 million. Reporter wow. Youve probably seen People Killed for a lot less. A lot less. Reporter and who would stand to benefit . Coming up i felt very early on that it was most likely a female. A closer look at susanne. You pull the knife out. And you tell the police right away, oh, youre going to find my fingerprints on the knife. A few million motives for murder . My mothers worth high seven figures. This is not the way i wanted to get my money. Its also a story about canals and the artificial heart,oers. Electric guitars and rockets to the moon. In other words, this is the story of america land of the doers. Doin it. Did it. Done. Hardworking doers and smartworking doers. Olds changed the way we put things together. And keepinem together . That was walters doin. Doers built this country. They built the dams and the railroads. John henry was a steel drivin man hmm, catchy. They built the golden gates and the empire states. Doers turn nothing into something. And something into Something Else. Doin got this nation done. Along with the hula hoop, blue jeans and that little thing we call the interstate highway system. And all this doin . It takes energy, no matter whos doin. Theres all kinds of doin up in here. Or what theyre doin. What the hecks he doin . Energy got us here. And its our job to make sure theres enough energy to keep doers doin the stuff doers do. To keep us all doin what we do. Peggy nadell had been murdered in her home in suburban Rockland County, new york. Detectives stephen colehatchard and earl lorence say the team from the crime lab had shaken peggys house to its foundation looking for a lead. Forensically, you guys got almost nothing off the scene . Not almost nothing, you know, nothing. Reporter no fingerprints . No fingerprints. Reporter no dna . No dna. No blood, no hair. Nothing. Reporter but the scene did tell them something. I felt very early on that it was most likely a female. Or two females. Reporter what pointed to it being women . The fact that there was seven or eight lacerations on peggys skull from the statue head. Reporter that statue is heavy, an effective weapon in strong hands. My nonmedical opinion is that if she was hit in the head with that statuette by a man, her head would have caved in. Reporter a man would have been able to swing the statuette harder . One or two times, at the most. Reporter and all of that pointed straight to peggys daughter, susanne. Not only did susanne stand to inherit half of her mothers 4 million estate, detectives thought her behavior was suspicious from the moment they arrived on the scene. Shes saying, my fingerprints are all over the knife. My dna is all over inside the house. Reporter and she was telling detectives the same thing she said during the 911 call, that it was an accident. I think my mother fell down the stairs and stabbed herself. Reporter in the 911 call, you are offering a theory of what happened. Thats very unusual. No. I thought she fell. Reporter secondly, you pull the knife out and you tell the police right away, oh, youre going to find my fingerprints on the knife, which sounds like somebody who is thinking ahead to the fact that that knifes going to get dusted for fingerprints. Sure. Sure. Reporter would you not agree that all of that is pretty suspicious when taken together . Maybe to them. Wasnt to me. I mean, obviously they formed an opinion from the getgo. Reporter detectives thought this was odd as well. She said, listen, maybe this was a burglary. Check for a large ring, a laptop and, jewelry. And i called to earl, check for these three things. He called me back and said, hey, pretty much those are the only three things missing. I asked about jewelry, i asked about her wallet, credit cards. If they said somebody murdered her, well, why . Why . Was it a robbery . Reporter so here you are offering theories again. Yeah. Reporter then again in those first few moments, susanne started talking about peggys money. One of the things she yelled out was, my mothers worth high seven figures. Reporter and this is not the way i wanted to get my money. Thats the exact words she used. Reporter this woman wants to talk her way right away. At one point, you said this is not how i wanted to get my money. I dont recall saying that. But if they have that on, you know, on record, you know . Reporter but you believe me that thats what you told police . Yeah. Reporter because, again, youre answering a question the police havent even asked yet. Uhhuh. I guess i watched too many of those dateline shows in the middle of the night. Reporter detectives had already talked to susanne and her husband bobby on the day of the murder. Questioned them for hours. Reporter but you had nothing to worry about. No. Not at all. Not at all. The farthest thing from my mind is that i would be a suspect or my wife would be a suspect. Reporter police were feeling differently, and as their scrutiny intensified, bobby and susanne decided to hire an attorney and stop talking to the police. Assistant District AttorneyRichard Moran said that slowed everything down. The best way to get information about the investigation would be through her. And once she stops talking to us, things take a lot longer. Reporter there was a point at which you and your wife stopped cooperating with police and hired an attorney. No. We didnt stop cooperating with the police. Thats what they want you to believe. Anything they wanted to know, alls they had to do was ask my attorney. Reporter your wife feels the same way about that . Oh, absolutely. Absolutely. She was just scared that they were gonna try and pin it on her. Reporter once again, susanne was right. We had, we believed, probable cause to arrest susanne. We just couldnt do it because something was wrong. Reporter whats wrong . I mean, everything points at her. It would have been the easy way out to do that too early. Reporter sometimes you get a ground ball. This wasnt a ground ball. Reporter this would be no easy out. Detectives would be going into extra innings. Coming up the two final phone calls of peggy nadells life. One came from a secret phone. These are the phones used by drug dealers, killers, cheating spouses. Thats correct. Could that caller be the killer . Four days after peggy nadells murder, family and friends gathered for her funeral. For peggys daughter susanne, it was all a blur. Whats it like to process both the fact that your mom was actually murdered and that youre the suspect . It was horrible. Horrible. I lost my mother. I lost my best friend. And now the finger is being pointed at me. As 80yearold peggy nadell was laid to rest today, her daughter suzanne scaccio has hired a lawyer. People in the area, its all they talked about. Reporter susannes friend, darcy greenberg, was hearing it almost every day. There were people who said she did it. Oh, she did it. Even i heard a neighbor yelled out, when are you going to arrest her for killing her mother . I mean, this is someone that probably knew us since she was a child. Reporter darcy was convinced susanne loved her mother and would never have hurt her. She was grieving. She was crying every day. She could barely get out of bed. She couldnt sleep at night. Reporter peggy nadells murder was now the biggest case ever to hit the Clarkstown Police department. We had the whole Detective Bureau on this and some other agencies, and ive never seen them work harder on anything in my life. Reporter perhaps because police couldnt talk with susanne, they stayed very close to her and her husband bobby. And very visible. They parked outside my house and sat. When i left, they left. When i came home, they came home. They were following my husband. Reporter did you think police were going to come put handcuffs on you . Yes, i did. I was sad, and i was scared. Reporter police even looked into susannes Shopping Habits and found something that intrigued them. Susanne bought her groceries at a nearby shoprite, a big supermarket chain. In fact, she was a creature of habit, visiting there 22 times in the month prior to peggys murder. But on the 23rd time, the night before peggys murder, susanne shopped at a different store, the one near her mothers house. What did she buy . She bought cleaning supplies, rubber gloves and some other items like that. Reporter had the crime scene been cleaned up . Detectives didnt think so. But still found it suspicious. Just before your mother was murdered, you go to the shoprite. Not the one near your house. The one near your mothers house. Mmhmm. Reporter and you buy rubber gloves and cleaning supplies. I did. I mean, i buy cleaning supplies all the time. I have a cleaning girl. She probably needed rubber gloves. She probably needed floor cleaner. Thats interesting. They knew what i bought. Reporter and detectives wanted to know more about who peggy might have had contact with in the hours before her murder. So they made this list of numbers they found on peggys home phone. And as they looked at them, one stood out. It was a call from an odd area code, and it came in at 1 17 in the morning. That was from what turned out to be a tracfone. Theyre commonly referred to as burner phones or throwaway phones. Reporter these are the phones used by drug dealers, killers, cheating spouses . Exactly. Reporter a few minutes after that tracfone call, the alarm at peggys front door was tripped. And at 1 23 a. M. , the Alarm Company called. Hello . This is the Monitoring Center with bullet security. This is peggy nadell. The code word is max, im sorry. Thats okay, maam. Everythings fine. Im glad everthings okay. Well disregard for you. Have a good night. Reporter it was probably the last time peggys voice was heard by anyone except her killer. Police were convinced still are convinced peggy was letting in someone that she knew. Susanne . Maybe. But why would she use a tracfone to get her mom to open the door in the middle of the night . She wouldnt have to let me in. I have a key. And i know the how to work the alarm. Reporter right. So if you wanted to kill her, you could have waited until she went to sleep and went in. Reporter unlocked the door and went in. Reporter disarm the alarm. There you go. There you go. Reporter police had warrants for all the family members phones. And a few weeks later they had boxes of records to comb through. Detectives analyzed susannes first. What could you tell about susanne from her cell phone records . A lot. Reporter investigator robyn arias from the Westchester County d. A. s office specializes in phone data analysis. I figured out a pattern of susannes life just based on her records. Reporter and on the day of peggys murder that day was like every other day in susannes life. There was no change for that particular day. Reporter and youd expect to see a change if somebody was in the process of committing murder for the first time . Correct. Correct. Reporter suggesting shes innocent . Either shes innocent or she has another phone. But there certainly wasnt communication that indicated that something was going to happen. Reporter as hot as detectives were on susannes trail, they had never stopped looking at the other members of peggys immediate family. You talked to peggys son jim and his wife diana right after the murder . Yes, when they came up. Reporter they live in florida . Correct. Reporter were they in florida at the time of the murder . Jim was in florida. And diana said she was in d. C. Reporter why was she in d. C. . She said there was a family wedding. Reporter and the records backed that up. When robyn arias looked at jims cell phone, it never left florida. Dianas phone records checked out, too. Where was dianas phone during that time . In d. C. Reporter thats it . Didnt move. Did not move. The phone went to d. C. , went back to florida. Reporter reasonable to assume that diana never left d. C. . Absolutely. Reporter but youre smiling. There was just a break. The pattern just was off. Reporter dianas records were speaking to arias, and detectives were about to get a break that would shift the direction of the entire investigation. Lets just say, this case was about to go south. Coming up that secret burner phone, who bought it . Who used it . Get ready for a whole new circle of suspects. So whats going on here . How many people are involved in this . Thats the question of the detectives working on peggy nadells murder had been looking at her daughter susanne. But now they were also looking at peggys daughterinlaw diana. Diana and peggys son jim had been married for 17 years. And while he may not have been that close to his mother, diana was always on the phone. My sisterinlaw used to call every morning. My mother would be on my phone with me and say, oh, i gotta go. Dianas calling on the other line. Reporter diana was a stayathome mom with two kids, leah and harris. Peggy doted on her grandchildren and would fly them up to new york to spend summers and holidays. Detectives had already confirmed that dianas cell phone had been in washington, d. C. , at the time of the murder. But when phone analyst robyn arias looked more closely at dianas calling pattern something seemed off. When she was in d. C. Her activity was just all over the place. Kind of the frenetic feel. There was definitely something going on. Reporter now arias looked at who diana was calling, putting names and faces to the numbers on her phone. She noticed diana suddenly ing seemed to have a lot of new friends in washington, d. C. A lot of people just popped up in dianas life for a very brief moment. Reporter arias calls them frequent users, people diana was calling repeatedly. What was also interesting to me about these frequent users is that they just had such different lives. Reporter diana was a suburban mom, and some of these people, well a lot of them had criminal histories living in d. C. Reporter remember, diana had been in d. C. For a wedding. Maybe these people were, you know, those friends of the groom you have to invite . So detectives got the guest list. None of the highfrequency callers were at the wedding. None of those people. Reporter and when arias looked at dianas phone records on the night of the murder, friday night into saturday morning the time of the homicide there was very little activity on her phone. Like eerily quiet. Reporter what did that mean . Dianas phone had been in d. C. That looked like a dead end. So detectives went back to that tracfone that had called peggys house moments before her murder. The kind of phone you can buy for cash, activate from almost anywhere and then dump when youre done. A lot of times thats a dead end. A lot of times. Reporter not this time . Not this time. Reporter to figure it out, detectives began by using the tracfone number to find where the phone had been sold. And where was it purchased . The Family Dollar store in miami, florida. Reporter miami . About two miles from dianas home. Reporter detectives contacted the Family Dollar chain and got very, very lucky. Family dollar was able to give them security video of someone buying a tracfone on january 23rd, just two days before peggy was murdered. Is diana on the tape . It doesnt appear so. Reporter so end of the road . No. Reporter no, because the woman buying the phone was someone detectives recognized. Not diana . Definitely not diana. Reporter who was it . Karen hammsamuel. Reporter and how did they know who she was . Karen hamm was somebody i had already profiled as a person who came up frequently on dianas call records. She was a High Frequency caller. Reporter so you got a friend of dianas buying the disposable phone that called peggy just before she was killed . Yes. That was a big moment. Reporter now they knew who had bought the phone. The next step was to figure out who had turned the tracfone on. Tracfones need to be activated using another phone to call an 800 number. After three weeks, detective colehatchard finally persuaded a tracfone manager to give him this piece of paper. He had circled a phone number. And it was the number that called to activate that tracfone. Reporter whose number was that . Andrea benson. Reporter had that name surfaced before . Yes, absolutely. All over dianas phone records. Reporter she was one of those people who had popped into dianas life when diana was in d. C. And benson had a rap sheet. So whats going on here . How many people are involved in this . Thats the question of the day. Reporter the other big question, what did diana nadell do while she was in washington, d. C. . Detectives started with her arrival at Reagan National airport 9 30 friday morning, the day before peggy was murdered. We got the video from the airport to follow her through the airport. And then follow her outside to where she got into a car. Reporter heres video of diana being picked up curbside. Who picks her up . Andrea benson. Reporter how do you know its Andrea Benson . Its her car, registered to her. Reporter you can read license plates with those cameras . Theyre pretty good. Reporter detectives obtained data dumps from cell phone towers in washington, d. C. , that allowed them to map the travel of the cell phones as they pinged off the towers. Can you follow dianas cell phone . It bounced all around washington, d. C. , simultaneously with andreas. They were together the entire day. Reporter by late friday, the night peggy was murdered, dianas phone stopped moving and went quiet. But andreas phone . We saw andreas phone head out of the Washington Area and head up i95. Reporter exactly the way you would drive if you were heading for peggys house . Right. Reporter along the way, the tracfone was activated. And at 1 17 a. M. , it pinged a cell tower right near peggys house. What was going on . Was this murder for hire . Did Andrea Benson drive up to new york, call peggy on the tracfone, somehow get into her house and murder her . Assistant d. A. Moran didnt think so. Peggy would never have let a stranger like Andrea Benson into her house. So that had to be a friendly voice on the phone . Yes. Reporter detectives thought that voice might have belonged to diana, but they had nothing to put her on the scene, in peggys house. At this point, is susanne off the hook . Diana is now the higher suspect. Susanne wasnt off the hook. Reporter they could be in this together . Correct. Yes. Thats where it was. Reporter because they both benefited. Absolutely. Yes. Reporter now eight weeks into the Investigation Detectives still didnt know who had killed peggy nadell. With suspects in florida, d. C. , and new york, detectives came up with a new strategy. And their phone expert liked it a lot. Gutsy. Like, i mean, a lot of people dont go to those lengths on a homicide case. I thought it was a brilliant strategy. Reporter but would it solve the case . Coming up did you have anything to do with your mothers murder . The daughter or the daughterinlaw . You think i killed my motherinlaw . Is that what youre telling me . Was one of them the killer . Oh, god, her eyes are probably about as big as the headlights on a volkswagen beetle. Three months after the murder of her mother, susanne nadellscaccio was still saying she was innocent and couldnt believe she was ever a suspect. You watch dateline. All the time. Reporter sometimes, as you know, people look guilty but theyre really not. Are you in custody right now . Nope. Reporter were you ever arrested . No. Reporter did you have anything to do with your mothers murder . No. Reporter deep into the investigation of peggy nadells murder, the prime suspect was no longer her daughter susanne. It was her daughterinlaw diana. Detectives knew that dianas friend, karen hammsamuel, had bought the tracfone that called peggys house just before she was murdered. Diana had told police from the beginning that shed been in washington, d. C. , to attend a wedding. But her alibi was wobbly. Diana couldnt account for her time in d. C. She hit washington at about 9 30 and didnt reappear again until about 8 00 the next morning. Reporter so detectives called diana, asking her to fill in the gaps. I just have to confirm that you were up in washington. Is there somebody i can talk to . What do you mean . We had to keep it real simple with her. Listen, we just want to get you cleared. Where did you spend the night . Reporter what did they not tell diana . Detectives had a warrant and they were tapping her phone. Police now sat back and listened as diana made multiple calls to people she knew in d. C. As she tried to find someone, anyone, you who would say they were with her in washington at the time of peggys murder. Was she ever successful enough to find somebody to say, yes, i will say, diana, that you were with me . Yes, she did. Yes. Which was her third attempt. Reporter detectives heard diana tell a female friend to say diana had been at her house in d. C. , but the woman seemed confused. So was it 9 00 in the morning or was it 9 00 at night until 6 00 in the evening . Right. Exactly. Which one . 9 00 at night to 6 00 in the morning. Okay. Reporter disorganized crime. Not the most intelligent people involved, i dont believe. Reporter sure enough, when detectives called dianas friend, heres what she said. Did diana stay overnight with you . Yes. She was with me 9 00 and she didnt leave until 6 00. Reporter of course, detectives already knew the woman was lying, and that diana was trying to cover her tracks. But they still didnt have enough to charge diana. So they headed to miami, to speak with dianas friend who bought that tracfone, karen hammsamuel. They brought karen into Miami Police Headquarters for questioning. All set . Reporter karen admitted she bought that tracfone for diana. Then they asked her if diana had said anything about peggy nadells murder. Her answer blew them away. She did say that she was there at the motherinlaws. Did she tell you who stabbed her . No. Reporter prosecutor Richard Moran was there listening in another room. And thats the first time we have firsthand information that diana was in the house. Reporter before long, diana was in that same miami Interrogation Room where she recognized some familiar faces she probably wasnt pleased to see. You know who we are, right . Yeah, why wouldnt i know who you are . Okay. Just making sure. Steve and earl. Reporter and she knew why they were there. You think i killed my motherinlaw. Is that what youre telling me . Reporter yes, it was, and after five months, their investigation was about to end. Youre under arrest for the murder of peggy nadell. I did not murder my motherinlaw. Reporter that same day, another team arrested Andrea Benson in d. C. Detectives lorence and colehatchard were confident they had the right people in custody and that susanne was finally off the hook. She heard the news from relatives. They said they arrested diana for my mothers murder. And that there were other people involved in it. And i was shocked. Reporter what did she look like . Oh, god. Her eyes were probably about as big as the headlights on a volkswagen beetle. And her instant reaction was, i knew it. I knew it. Reporter susanne says her mom had been sending money to diana regularly to pay for home repairs and expenses for the kids, but she says diana wanted more. She wanted to live my mothers life, do all the things that she couldnt afford to do. Reporter and to do that all she had to do was enlist the help of a few friends and commit a murder. Uhhuh. Yeah. Reporter detectives didnt think jim knew anything about his wifes deadly plan for his mother. And what exactly was her plan . Diana had stopped talking and asked for a lawyer. But her friend Andrea Benson, did talk and told d. A. Richard moran the whole sordid tale. Andrea said she had never met diana before and had been told by a relative to pick diana up at the airport and, as they were driving diana nadell said to her, im not really here to go to a wedding. Im really here to kill my motherinlaw. Reporter she says this to a person shes never met before . Yes. Reporter and Andrea Benson says, okay, im in . For 10,000. Reporter and right there the deals done in that car . And the plan starts taking shape. Reporter benson said she drove the four hours up to peggys house, and then diana used that tracfone and called her motherinlaw. Diana tells her, im here. Dont you miss me . I want to come see you. Reporter at 1 30 in the morning and peggy lets her in. Benson said she went in with diana. They were wearing hair nets and gloves to keep from leaving evidence. Diana and peggy sat across from one another and talked. Benson said at one point, peggy went upstairs, perhaps to call for help. She and diana followed her. Then, as peggy came back down stairs thats when Andrea Benson started choking her. Reporter andrea said peggy was still alive when diana hit her motherinlaw with a metal ball and beat her with that statue head. Andrea bensons words were, she wouldnt die. At that point, according to Andrea Benson, diana nadell went into the kitchen, got a knife, came over and started stabbing peggy. Reporter Andrea Benson pleaded guilty to firstdegree murder. The sentence was 20 to life. I need you to know just how sorry i am. Reporter the woman who bought the tracfone, karen hammsamuel, was never charged with anything. Diana, apparently not content to wait in jail for trial, was caught on tape trying to arrange for hit men to kill karen hammsamuel in miami. Tell them i said its absolutely imperative. The one in miami hes got to get rid of. The one in miami. Right. Reporter after that, diana also pleaded guilty to firstdegree murder. Diana did not respond to our requests for an interview. She did speak on the day she received a sentence of 23 years to life. I would like to say that im very sorry for my actions and that i am extremely sorry for any pain i may have caused, especially to my husband. Reporter susanne was there at sentencing. You took away a wonderful mother and grandmother. And youre going to die in hell. I hope you stay in prison until you take your last breath. Enjoy prison. Reporter on mothers day susanne and bobby went to visit peggys grave. Hey mama. Reporter finally it was all over. You kind of look at life a little bit differently. You know, life is very valuable. Its precious. It puts things and perspective. Reporter you done anything special for yourself . I treated myself to a car. Shes a fancy german lady that likes to go fast. My mother always said, spend a little. Enjoy your money. Youll have mine some day. Who knew that some day was going to be so soon . Thats all for now. Im lester holt. Thanks for joining us. Nbc bay area news starts now. Right now at 11 00, the video that has outraged people nationwide. Dog abuse caught on camera. Now the local effort to catch a woman who did it. A bitter cold night with no heat. Thats what thousands of bay area residents are facing. Well show you how theyre coping. A live look at san jose right now. We have rain in the forecast for bay area. What you can expect for tomorrow mornings commute. Good evening, everyone. Im terry mcsweeney. And im peggy bunker. We start with that developing story in discovery bay. As the sign here says, 6200 people do not have access to gas heat right now. You can blame this near freezing weather for that