there was no fear of anything. i don't know if something snapped. i was shocked. i couldn't say anything. >> a doctor comes home but not for long. an hour later, she was back at the hospital she just left. >> she had this blank stare in her eyes. >> three days later, she was dead. >> i said, she is my child and i gave birth to her and i want to know what happened to her. >> at first, it was just a medical mystery. >> for all intents and purposes she should be alive. >> it was out of this world. it made no sense. >> but soon, it became a murder mystery. because once they discovered what killed her, the next question was who. >> if he couldn't have her, no one was going to have her. >> i still have it made sense of it. welcome to "dateline." the doctor was in the business of saving lives but the doctor became a patient one out of the blue she collapsed and was rushed to the e.r. now the seemingly healthy woman in the prime of her life was fighting for her life. it was a medical mystery or was it? this is the case for doctors in the police here is dennis murphy with lethal weapon. the emergency room trauma team was losing her. she had been wheeled in and gasping for breath. >> her heart stopped. we had to restart her heart. >> within minutes, machines were doing the breathing and blood circulation for the 41- year-old. wife, mother, medical doctor, a rising star in the field of women's neurology. a star whose light was beaming even as they tried desperately to keep her going. >> these are doctors who are treating trauma patients every day. this one had totally puzzled them. >> the woman bailing in the e.r., doctor matt klein, was in many ways what modern pittsburgh was all about. the downtown powers didn't need to worry anymore about remedies that the steel mill smokestacks along the river. the steel industry here had mostly died by the early '80s i moved overseas. universities, technology, medicine, finance, that was the foundation of the new pittsburgh they called the renaissance. robert and his wife relocated from boston and were the kind of minds the city was hoping to attract. autumn's colleague, -- >> she said she loved pittsburgh. she loved her patients. >> the people of pittsburgh were wonderful and she was so happy to be there. >> autumn had intended to be a caregiver. her cousin remembers that even as a little girl she administered playtime tlc. >> we have a doctor's office and our patients for our stuffed animals. >> and she was holding clinic hours. >> she was a doctor. >> it was an interest that took root early and never left, and always at the top of her class. she later got her undergraduate degree in neuroscience. >> helping people was the main thing. she was just so smart and so intelligent and thoughtful and caring. >> you and your husband must be very proud of her. >> we were. >> lois klein is her mom. >> we knew she was putting her mind on her study and we were giving her the best education we could possibly give her and she was taking advantage of it. >> med school was a certainty. she announced she was heading to boston and her mother worried that the crime rate was too high. >> she said, i am going to boston university medical school and i said, no you're not and she said, yes, i have and i said, no you're not and she went to medical school in boston. >> she developed a reminding thing for a colleague and heat for her. he held a phd in neuroscience and was hunting for tours to brain illnesses like lou gehrig's and huntington's diseases. he was also more than 20 years her senior. divorced with two grown kids. >> i simply told her that was a little too old for her. i didn't think that was the right age. >> two days before graduation from med school, a determined autumn wasted no time and was walking down the aisle with her much older room. >> what was your impression? >> nice guy. >> nerdy? >> yes. and she kind of was and kind of wasn't. >> they made a home outside of boston and in a few years a baby girl arrived. autumn took it in stride. >> hum diaper changes nothing for her. i mean, a call from the hospital, you have to take care of the patient. she is used to that. >> the new mother was becoming a sought after specialist. but she was growing frustrated with boston and professionally she felt as though she had crested there. that is one pittsburgh looped interview. in 2011, the university of pittsburgh in the medical center offered a career move. for bob, a research lab and for autumn, a check to head her own department. >> autumn was not just a rising star, she was a shooting star. she was nationally recognized as a leader in her field at a very young age. >> but still something was gnawing at her. a kind of emotional vacuum. she wanted to have another child in in her early 40s, she was taking fertility treatments but nothing was happening. >> wasn't really eating away with her that she wasn't getting pregnant? >> yes. and just speaking from experience, fertility treatments are the loneliest place a limit will ever go. >> looking back, her mom recognizes now some worrisome signs. changes in her daughter. >> i kind of saw she wasn't herself too much anymore. she was kind of a little, what you call it? kind of down, maybe. >> in early 2013, they tried a new approach to the baby problem. a fertility doctor thought the supplement note as creatine might help autumn get pregnant. as it turned out, her husband had been using the stuff it is research. so on april 17th, autumn, was ready to give it a try. she texted her husband that day. i ovulate tomorrow. he answer, perfect timing. these are hospital security camera pictures that show autumn throughout the day and leaving work that night. 10 minutes later, she was home and minutes after that, her husband was on the phone to 911. >> hello. please, please. >> his wife was gasping for breath. the dispatcher asked the husband what he was seeing. >> i think my wife is having a stroke. >> paramedics arrived at the home to find a woman in very bad shape. >> she was lying on her back on the kitchen floor. her eyes were open and she was unresponsive. >> an hour after walking home from the medical center where she worked, was back as a patient in its emergency room. and whatever was happening to her was a medical mystery to the team trying to keep her alive. then they saw the blood. out of the experience. so read. >> autumn is surrounded by some of the best doctors in the country but no doctor can work miracles. coming up, maybe someone else could. when "dateline" continues. including those with asthma, diabetes, copd, and certain other conditions. but i'm protected. arexvy is proven to be over 82% effective in preventing lower respiratory disease from rsv and over 94% effective in those with these health conditions. arexvy does not protect everyone and is not for those with severe allergic reactions to its ingredients. those with weakened immune systems may have a lower response to the vaccine. the most common side effects are injection site pain, fatigue, muscle pain, headache, and joint pain. i chose arexvy. rsv? make it arexvy. icy hot. ice works fast. ♪♪ heat makes it last. feel the power of contrast therapy. ♪♪ so you can rise from pain. icy hot. the best moments deserve the best eggs. especially when they're eggland's best. taste so deliciously fresh. with better nutrition, too. we love our eggs any style. as long as they're the best. eggland's best. dr. autumn klein had been rushed by ambulance to the e.r. of the university of pittsburgh medical center after slumping to the kitchen floor of her home. >> we thought there was a possibility of a stroke and we knew she was in critical condition. >> now the trauma team was trying to keep her vital signs going. alan jennings, at the time a reporter, covered the story. he re-counted what doctor said about that night. >> she had this blank stare in her eyes. barely oppose. they didn't know what happened to her. >> autumn was struggling to breathe. >> then incomes the ventilator. >> the machines are taking over. >> to keep her alive so they could determine what in the world was going on. >> at some point did they realize this is one of their own? a brilliant young doctor that works in the neurology unit? >> they did at one point. i don't think they would have treated anyone differently but she was one of them. one of the team. >> when her husband bob ferrante arrived, he tried to give the team some of his medical history. he explained she was on fertility hormones. >> she had headaches, fainting spells, and she generally was expressing she hadn't been feeling well. >> he told the e.r. doctors he thought his wife was suffering a stroke though diagnostic test set otherwise. by then, bob ferrante had already called his father and mother-in-law at their home near baltimore with the bad news. autumn's mother said they got in the car immediately to drive through the night to pittsburgh. she was counting out the exits. >> i said, please let me get to frederick and then let me get to hagerstown. please let me get to hancock and please let me get to pittsburgh. >> back in the e.r., a resident trying to rally her body stuck an iv into her and noticed something quite odd. her blood in the tube showed shocking red. the observation? this blood is to read? why am i seeing blood this brilliantly red? >> to them this was out of this world. they could not make any sense of it. >> eventually, autumn went into cardiac arrest and doctors managed to bring her back, barely. >> they took turns doing chest compressions to try to get some reaction from her and get her heart moving and pumping again. >> another doctor reviewed her symptoms and ordered tests. he wanted a toxicology and hours passed and her blood was being pumped into a machine that was doing the oxygenating work of her heart and lungs. at some point, word reached her cousin now living in washington state. sharon talk by phone to her husband bob and was paid for his medical background. >> he was calling his colleagues and it was great to use those resources. i have no idea what's going on. >> eventually, autumn lost rain function and by the time her parents mated to the hospital, they could see there was little hope for their daughter. >> they had a lot of tubes and things hooked up to her. i held her hand and i talked to her. and i told her, you heal everybody else's brain, why can't you heal your own? >> sharon wanted desperately to fly from washington state to see autumn, and her aunt lois told her to wait. >> that's my other half in that hospital bed. i need to be there. >> doctors managed to keep her alive for two days but at some point to tell that her grieving husband had run out of hope. >> he did say that he was going to spend the last night with the love of his life. and at the time i thought, it's not over yet. >> but in the e.r. suite, everyone knew it was. autumn's little girl was brought to her bedside. >> she made some comment to somebody about i don't think mommy is ever going to come home again. >> on the third day, they pronounced her dead and turned up the machines keeping her alive. >> a lot of my life feels like it doesn't make sense without her. she was there for everything. >> autumn's husband and family now had funeral plans to make and darker days to get through but one person wasn't done with the case of autumn klein. his work was just getting started. the doctor, and associate medical examiner, performed the autopsy on autumn. >> it was regarded as an unexpected death. >> which meant the county needed to figure out why this otherwise healthy woman was dead. there was no reason to suspect fertility hormones, vitamins or supplements could have led to her collapse. her brain showed no signs of a stroke though an examination of the heart revealed an abnormally shaped heart valve. >> it is an anomaly found in approximately 2% of the population. >> doesn't lead to early death? >> not in your 40s. >> at the conclusion of the autopsy they were perplexed as to what killed this woman. >> i'm not seeing anything. i see a healthy white female and for all intents and purposes should be alive. >> on the form that asked for cause of death, he wrote, pending. no definitive answer, but in a few days he would have more information. the bloodwork was back from the lab. autumn klein had suffered a very unnatural death. >> coming up. what exactly had killed autumn. >> i was shocked. i couldn't say anything. >> or is the question, who? when "dateline" continues. director: cut! jordana, easy on the gas. force of habit. i gotta wrap this commercial, i think i'm late on my payment. it's okay, the general gives you a break when you need it. yeah, we let you pick your own due date so you can pay your car insurance when it's best for you. well that's good to know, because this next scene might take a while. 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>> that tells me we have a cause of death now. >> sinai, the poison of the nazi death camps and not a common cause of death. >> i have done approximately 3500 cases in my career and this is my first case of cyanide poisoning. >> the toxicology work that levels of 3.5 milligrams -- 3.35 milligrams in autumn's blood. still, he needed to confirm the result with his own tests. he wanted to re-examine her remake to see if he could find cyanide in other parts of her body. but by then, he related to the funeral home. >> here's an easy solution. you go back to the body and take a second look >> we would love to, but when we got the phone call on tuesday, i called immediately to the funeral home and she was cremated. >> but they had samples of her blood. it's toxicology unit performed its own test for sinai. analyst alicia smith added a simple solution to the blood and if it was present in the sample, it would turn the center well of this this purple. she and luckasevic demonstrated what they found. sure enough, the sample change color. >> the color change was a deep dark purplish pink. and it was obviously positive for cyanide. any amount, even though one milligram per liter and a light pink color change means there is cyanide there and a lethal amount. >> autumn klein had died of cyanide poisoning, no question about it. he grew even more confident when he reviewed the details of how she collapsed and suffered. once ingested, it can quickly starve the body of oxygen. >> oxygen is on the blood but not being utilized by the body. >> it was the trapped oxygen that turned the blood that vivid red. he also considered the 911 call. the husband is begging for help and autumn can be heard moaning in the background. luckasevic says that is likely autumn trying to breathe and even though was that -- a bizarre death, he contacted the police. >> i let them know the cause of death is cyanide poisoning. >> he wanted to know if autumn committed suicide or was poison. in other words, murdered. >> there was a note on my desk saying the coroner's office had a woman come in who had a lethal level of cyanide in her system. >> how many of those have you seen in your career? >> it is my first one. >> soon, autumn's mom was given the news and then she called her knees in washington. she said, are you sitting down. i said okay. and she said it was cyanide. >> just like that? >> and i was shocked. i couldn't say anything. i couldn't catch my breath. >> when autumn's colleague heard about it, she knew right away her friend has suffered an agonizing death. >> as a medical professional, i know how people die of cyanide poisoning. and i couldn't dwell on that. >> just said in an old agatha christie murder mystery about a cyanide poisoning in the village, the inspector was about to call. pittsburgh senior investigators were en route to talk to robert ferrante. did he have any idea how cyanide found its way into the stream of his late wife. >> coming up, a husband theory of how and why his wife died. what was he suggesting? did he know something the police did not? when "dateline" continues. it's an add-on treatment for specific types of moderate-to-severe asthma. and can help improve lung function for better breathing in as little as two weeks. dupixent helps prevent asthma attacks... and can even reduce or eliminate oral steroids. can you picture it? 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>> why would she do this to herself? >> that's correct. >> to the cops it looked like he was suggesting his wife had committed suicide. ferrante then told them about her trying to get pregnant and failing. she was taking a supplement called creatin hoping it would help. the detective understood the emotional agony. >> she's trying to have another child and that is a lot of stress on a woman. >> could autumn's distressed state of mind have led to suicide? the texas had to consider that as a theory. cyanide is an unusual way to kill yourself and hard to get poison. how could autumn have gotten her hands on it? >> we looked into the labs where she worked and she didn't work in a lab. she worked with patients. >> she was a clinic doctor. working hands-on? >> yes. >> but there were other labs stuck with poisons including cyanide at the complex. maybe autumn wind murdered into one of those. detectives pull security cameras from the footage -- and here's what they saw. that is autumn as she's getting ready to leave work. she goes up a set of escalators, disappears for six minutes before coming back down and heading home. in those minutes missing from the camera, did she find her way into a lab with toxins? >> maybe this is where she goes to get her hands on cyanide to inexpressibly -- and explicitly -- the investigators learn that to get into any of those labs, autumn would have needed a special card. is there any sign she had a card swipe to put her in an area where someone might've had cyanide? >> no. >> the more they don't, the less they believe this unexpected death was a suicide. autumn was frustrated by her infertility, but this appointment was all it was trying to her cousin sharon. suicide was never on her radar. >> that was not autumn. >> family, friends and colleagues agreed. autumn was a woman with plans to live, not die. she had a daughter she adored and was scheduling vacations and research projects just before her death. if she didn't take it, and the theory she hasn't killed herself, the only place to go is homicide. >> that's correct >> who would want to murder autumn klein? the spouse is always a suspect until they are not, but the husband here, bob ferrante, was a renowned medical researcher and didn't fit the bill. in fact, the marriage appeared to outsiders to be a good one. still, detectives had to consider the husband's line of research. he worked with toxins in his lab but not cyanide. more than a week after they interviewed the husband, detectives began talking to his lab associates. >> the people we talked to said there was no research with cyanide. >> yet, detectives were just getting started with their investigation. they interviewed friends and colleagues and reanalyze hospital footage. >> once they got all that together and got all the pieces of the puzzle together we had our picture. >> a picture that revealed only one person who had the motives and means to kill autumn klein. her husband bob ferrante. though the evidence was circumstantial, three months after her death, they were ready to make an arrest. at the time, bob ferrante was visiting his sister in florida. they had us out to make the arrest. but when they got there, the sister said ferrante was gone. >> she said he got a phone call from an attorney and he got in the car and said, i got to go. then he left. >> do you think he was running? >> he was trying to get away. >> yes. yes. we were told he was going to his attorney but he is running from us. >> in your bookie is a fugitive? >> yes. >> but not for long. as it turned out, he was on his way back to pittsburgh . when he was pulled over by state police in west virginia and later handed over to pittsburgh authorities. police had their man and they had to prove to 12 men and women that he was the right one. >> we had a clean case. >> the judge who would preside over it all, the case against bob ferrante was far from a sure thing and could lead jurors scratching their heads. >> i would not have predicted a verdict here. >> it could have gone either way and you wouldn't have been surprised >> that would be correct. >> coming up, was jealousy a possible motive for murder? what had bob ferrante discovered about his wife? when "dateline" continues. well, rest assured, company's in great hands. marci, hit the vid'. 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not me. my own real tears are my relief. ask your eye doctor about tyrvaya. here's morikawa in a tough spot. off the comcast business van. look out! where did the ball go? oh, wait there it is. back in to play! and that's in! what an impossible shot! dr. autumn klein and robert ferrante had all the trappings of access and happiness. prestigious jobs. at one time, it all seemed enviable. did you think they were a good couple? >> yes. i did. >> then it all went so wrong. autumn, dead from an apparent cyanide poisoning and her husband a year and a half later standing trial for her murder. even to the presiding judge, this was a first. >> it was an intelligent man who was accused of poisoning his wife. experts who argue with one another. very good lawyering and good experts. >> it would be up to the prosecutor to explain what drove an otherwise mild- mannered scientist to kill the wife he supposedly loved and in such a cruel manner. she opened by describing a man infuriated, one losing control of his more successful wife who had grown tired of him. >> a reporter was in the courtroom. >> prosecutors say he was obsessed, jealous, and his marriage, he realized, he was going to be dumped by his wife. >> the prosecutor asserted that the marriage was in free-fall at the time of her death. and he had checked out, especially when it came to the issue of having another child. >> my husband is a psychologist and she said i need you to ask him if there is a gene for compassion. if there is, then is lacking it. >> that just describes acres of sadness, doesn't it? >> yet. >> the prosecutor showed an email that autumn sent in the month before her death broke, i realize now i have been alone in this entire emotional journey. i can't even speak to it that getting angry. did she ever say she's going to leave him? this isn't working? >> yes. she did to me. >> he was positively rattled to the court said the prosecutor when he found out that autumn was texting and emailing a male colleague. bob ferrante expected his wife was having an affair and autumn's cousin was sure that wasn't true. >> if this is somebody she was remotely interested in, she would have told me. >> you don't think anything physical is happening? >> no. >> but as the prosecutor told it, the defendant believed otherwise. rather than ensuring up a crumbling marriage, the embittered scientist, and his wife came up with a cold- blooded solution. he poisoned her. >> the motivation just jealousy. if he could not have her, no one was going to have her. >> ferrante , the prosecutor said, could get rid of his wife quickly by slipping her cyanide. when she didn't die immediately, he had to come up with a plan b. the prosecutors played the 911 call. >> i think my wife is having a stroke. >> they were establishing his attempts to lead everybody he encountered starting with the 911 operator. he said, i think she's had a stroke. steering it. >> then went autumn died, according to the prosecutor, ferrante is something he thought would keep the cause of death secret. lois klein testified her son-in- law said lightly he did not want an autopsy. >> i said i am her mother and i want an autopsy. i said i can't believe you don't want to know what happened to her. in his response was, people do that. they do autopsies and then the people don't want to know the result of it. so, that was that. >> the prosecution described the man who lost control of his wife, killed her and tried desperately to cover it up. the defense attorneys. you get the picture of a jealous guy whose career is being eclipsed by his wife and he thinks she has a lover and she's dead. >> that's not really the case for >> they said it made for great melodrama but miles away from the truth. >> bob was very successful and on the verge of some big breakthroughs. >> he was a brilliant researcher and loving man devoted to helping his wife, not hurting her and to sell that they called the defendant himself to the stand. >> in this case, the defendant made that choice. i've often said it's risky at best the minute the defendant take the stand, we now have the government versus the defendant 's credibility. >> he wanted george to see him for the man he was. one who loved his right complicated wife. >> he wanted to help the jury understand what was going on in their marriage and tell them how badly his wife wanted to have a child. >> yes, he conceded, he was a jealous husband or a brief moment but they kissed and made up in the weeks before her death. >> they go on a trip to puerto rico with her daughter. as the neighbors describe when they come back, they are going and in love and holding hands. those actions speak 1000 words. >> in the moments after his wife collapsed, he thought she was having a stroke. when she died, he wanted simply to honor her wishes and donate her organs and that is why he did not want an autopsy. >> he was aware that if an autopsy done, it would destroy the ability to donate organs which was his wife's requested >> a loving and loyal husband to the end according to the defense. not a mad scientist treating his wife like a lab rat killing her with cyanide. they said the claim of how she died was all wrong. >> there is not evidence that my client had anything to do with her death. let alone her death caused by cyanide. >> and age-old poison with a connection to a medical research and dock your wife said they were about to be analyzed under a different kind of microscope. the unforgiving eye of the law. >> coming up, with someone as smart as transport you something as obvious and easy to trace as cyanide? 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prosecutors believe he slipped the cyanide inside a drink and gave it to her shortly after she came home that night. at theory that was tough to prove. >> no one said there with her two eyes and said, i saw him put the cyanide in the drink and give it to her. >> that is a weak point in the prosecution. >> keep in mind, circumstantial evidence is very powerful. >> prosecutors told the court that he used his wife's motor ability to trick her into taking cyanide that night. earlier in the day, she sent him this text message. creatin. this is the solution. >> he convinced his wife that creatin could help her get pregnant and whipped up a drink knowing she would take it as soon as she came home. the drink theory was corroborated by something told later to a doctor friend. >> he told him he said, i don't know. i gave her hey creatin drink and she passed out on the floor. >> no one may have been the wiser for it if it hadn't been for a lab test that found in amount of cyanide in her blood. subsequent tests were also positive for the poison. the associate medical examiner dr. todd luckasevic underscored that for the jury. what caused the death with cyanide poisoning. >> no doubt. >> nor was there any doubt said the prosecutor as to who poisoned her. police discovered his laptop hidden in an office safe and incited a wealth of information that told them he was a very busy researcher in the months before his wife's death. >> he was googling and searching for things concerning cyanide. where to purchase it, the effects on people. >> and he didn't stop there. the prosecutor said bob ferrante made an interesting a crack -- request , something later relate to detectives. >> he tells this person that he wants to order cyanide. has he ever done that before? never. >> better yet, he asked for it to be delivered overnight. >> this is two days prior. >> he even left his fingerprint on the container which interest linked to them had a .3 grams of cyanide missing. like a heaping speed teaspoonful? >> i think a teaspoon full. >> is that a lethal amount? >> yes. >> the prosecutor said the defendant thought he was so smart pulling his wife and that everyone else by using a poison he assumed was untraceable. >> standing and looking at the jury, points to ferrante and that man right there, was one blood test away from the perfect murder. >> what murder? he said he did not commit a crime because there was no crime. >> i said as forcefully as i could, we don't believe and will never believe that autumn klein died from cyanide. >> the defense was attacking the cornerstone of the case. blood test could never be trusted they said. >> there is no way that is the results of the lab. >> out? >> yes. >> because they screwed up with the calculation. they only caught the error months later correcting it to 2.2, but still a lethal amount. >> it raises a real issue of credibility. and gives the defense something to work with. >> far more reliable argued the attorneys was another test done the week after her death. it found cyanide in her blood but at low levels. nowhere near lethal. in this case, that alone was more than reasonable doubt for the jury to acquit. >> reports are highly conflicting. >> the defense introduced the legal mix a renowned pittsburgh internationally recognized pathologist. he weighed in on cases from the jfk assassination to the death of elvis presley and jonbenet ramsey. he told the court that test amended a tiebreaker. >> what you do is send it again for laboratory testing, preferably to a third highly respected toxicology lab. that was not done. >> more compelling was evidence of scarring around her heart which could have triggered an electrical malfunction stopping the organ cold. only on the spot cpr could've saved her. >> in the absence of somebody hitting you in the chest and knowing what they are doing, you probably will die. >> in other words, the defense said autumn could've died of natural causes. they added that crime scene tax process the house and never found a trace of the poison. and their clients searches done for research purposes. not murder. here he is in january asking questions of google about the nature of cyanide. this looks very bad >> in april is asking about cyanide, for science research. >> the defendant further explained his actions from the sand. he ordered the poison for work and took it out of the box when it arrived. that is why his fingerprint was on the container. besides, his lawyer added, a man as smart as bob ferrante would never use a weapon next okay easily be traced back to him. >> that's like me buying a shotgun and telling everybody i bought a shot and two hours later my wife is dead from a shotgun. >> enclosing they begged the jurors to use common sense which said is exactly what they did. their common sense and the science presented told them autumn klein died of cyanide poisoning because the defendant had given it to her. they found him guilty of first- degree murder. >> crushing. especially in this case. absolutely crushing. >> yep. good description. >> bob ferrante was sentenced to life in prison. at the time of this interview, autumn's family felt they got justice. their anger was overshadowed by all the what ifs. >> not only do i grieve autumn, but also her patients. my heart aches for her patients. >> it was all she had ever wanted to do. help others. now that chance is gone. swept away way too soon. >> that's all for this edition of "dateline." thank you for watching. good morning, and welcome to this sunday edition of morning