>> then suddenly she was gone. a mystery illness that baffled even her doctors. >> she shook like someone with the start of parkinson's. >> what had killed her? something at work? something at home? >> household items, that's a possibility. >> listen carefully. in this case, the most important clue of all just might come from the victim herself. >> could this be murder? >> do you think that he tried to poison you? >> it sounded like a very unpleasant way to die. >> yes. >> and could she help solve it? >> you're describing a murder in slow motion. >> elaborate, diabolical. it's mind boggling. >> hello and welcome to "dateline." linda curry was thriving with a dream job and a dreamy new husband. then she got sick, and doctors were stumped. but what started as a medical mystery soon took a sinister turn. a lab test revealed one piece of the puzzle, but it would take investigators years to put all the pieces together. here's josh mankiewicz with toxic relations. >> reporter: what was wrong with linda curry? >> something's happening to you, linda. you're ingesting something that's in your body that shouldn't be there. >> she went to the doctor, a lot of doctors. >> and it wouldn't go away, and it would get worse. nausea, vomiting, dizziness, confusion. >> medicine didn't seem to help her. >> you could have respiratory failure within a number of minutes. >> those who knew linda watched something unfold. but what exactly did they see? it would take 20 years to unravel this mystery. linda curry, born linda kilgore, was six years younger than her sister pat. linda grew up to be a southern california beauty. she loved the sunshine, horses, and family. pat's daughter ricki ryecraft looked up to her aunt linda. >> she would call me to come to her house and raid her closets and i would leave with my back seat loaded from the floor to the roof with clothes. >> she sounds like a lot of fun. >> she was a lot of fun. she was a blast. >> linda worked for the power company, southern california edison. that's where she met mary seibold. >> where we met was on the fourth floor where we ate lunch: she ate like a horse and never gained an inch. >> you see people like that? >> we became the best buds ever. >> looks, generosity and brains don't guarantee happiness in love. linda was married twice and divorced twice. >> she did choose guys that didn't seem a nice fit for the long term. >> and so she got her heartbroken a couple of times? >> she got her heartbroken more than a couple of times, yeah. >> but if her personal life wasn't going well, her professional life was. she climbed the ranks at edison, becoming the training coordinator at the san anofri nuclear power plant. it was there linda met a man named paul curry. he was 13 years younger than linda and worked as a nuclear physicist. paul's boss, mike flower. paul had an impressive resume. >> yes, he did. and a good reputation. he had a senior operator license. that's not such an easy qualification to, to find. >> and just a few months before linda and paul started dating, he'd won $24,000 on jeopardy. so he's this younger guy. >> younger guy. >> gourmet cook. >> gourmet cook, a peaianist. >> he's in mensa and nuclear physicist. >> all the right things. >> they moved into picture-perfect san clemente. they said their marriage vows in 1992. that part about in sickness and in health would be tested less than a year later. in the spring of 1993, linda came down with an illness that put her in the local hospital. mary came to see her. >> she looked like a little girl in a big bed. she just looked so weak and not vibrant like linda. >> frightening to see her like that? >> yeah, you betcha, you betcha. >> her newly minted husband paul was sick, too, with many of the same strange symptoms. both were weak, vomiting, like bad food poisoning or the worst stomach flu imaginable. paul recovered quickly. linda did not. >> we knew that she was very sick and that they couldn't identify what was causing the problem. >> paul kept a vigil bit her bedside and kept their edison colleagues updated with daily emails like this. there still is not much clue as to the original infection, but if she continues to improve and gets well soon, i don't think it will really matter what the name of the problem was. i think we can all live with a mystery as long as linda's around to be mystified with us. how was paul when linda was sick? >> very concerned. >> worried? >> yes. >> eventually linda recovered enough to go home. paul fixed her gourmet meals. drew her a hot bath every night. and soon linda went back to work at the san anofri nuclear plant. months later she was in the hospital again, same strange symptoms. linda recovered enough to go home and back to work, but she worried about a relapse. she and paul planned to meet with some specialists who might be able to help. on june 9th, 1994, paul emailed mary. >> it was, gee, mary, i'm really worried about linda. she's wobbly and weak. >> paul wrote that she was mumbling incomprehensible stuff in her sleep about work and projects and meetings. >> and she's working all these hours and she's working too many -- and maybe, mary, she'll listen to you. >> when linda came home from work that day, she was tired and went to bed without eating dinner. a few hours later the phone rang at mike flower's house. >> i answer it. said, mr. flower, this is the chaplain. and he said, can you come to paul and linda curry's house? >> mike rushed over and found his friend paul, who told an awful story, how he woke up to an odd sound. found linda not breathing. he called 911, but by the time paramedics got there, it was too late. >> paul was extremely upset for hours. i was basically holding him up and he was crying on my shoulder. >> grief, shock, and at the bottom of it all, a question. what killed linda curry? >> coming up. linda's loved ones would wait years for an answer, an answer that would come. >> linda lee curry. >> from linda curry herself. when "dateline" continues. 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talk to your asthma specialist about dupixent. if your financial situation has changed, we may be able to help. everyone who knew paul and linda curry knew that linda had been sick for months, an illness her doctors could never explain, and paul had been sick, too. now suddenly linda was dead. paul's friend steve whitley. >> everybody was in such shock. i don't think the reason mattered. it was just, okay, we've got to take care of our friend. >> how was paul? >> grief stricken. >> so was linda's family. her niece ricky remembers how paul changed the funeral arrangements to help them deal with linda's sudden death. >> he allowed the casket to be open so my mom could see her sister, wrap her mind around her sister being gone. >> linda was now only a memory, but she'd left behind a perplexing medical mystery. what caused the mysterious illness that took her life? what were her symptoms? >> diarrhea, vomiting, dizziness, fatigue. >> and it wouldn't go away? >> it wouldn't go away. >> after linda's death, they discovered a medical chronology on her computer at work. she'd kept careful notes about her symptoms from the very beginning. it went back a year to june 28th, 1993. she wrote, felt fine all day. worked late. had a salad for dinner. woke up in the middle of the night vomiting. a month later, july 24th, 1993, approximately one hour after eating, i began vomiting. i became extremely weak and sweaty. linda's best friend mary seibold. she worked at a nuclear plant. >> she did. >> conceivable that maybe something she picked up there had something to do with it? >> that's not what happened. unless you're in the reactor. >> she never did that? >> no, not at all. >> they considered other darker possibilities. you know there are people who make themselves sick because they want to be the center of attention. >> sure. she wasn't of that personality. >> possible she was depressed? >> she loved her job. she had friends. >> she had the perfect husband? >> perfect husband, lot of nice high heels, what's to be depressed about? >> linda's autopsy was inconclusive. her death certificate listed the cause as pending investigation. and sheriff's detectives did investigate. >> taking place at mr. curry's residence. >> in december 1994, six months after linda's death, they interviewed paul. >> did you ever question him why they never found -- >> sure, both. we were making ourselves hysterical trying to figure out what was going on. >> like everyone else in linda's life, paul said he was puzzled and frustrated. >> i've been a problem solver all my life, and for the last couple years there was a problem i couldn't solve and extremely taxing. >> and like everyone else, he wondered if postmortem tests would finally solve the mystery. >> do you understand the family is protesting -- >> they haven't sent me any information. >> jones is a forensic toxicologist at the boston university school of medicine. she didn't work on linda's case, but in her lab she often deals with the same challenges when finding out how someone died. linda suffered from dizziness, weakness, vomiting after eating. what's that sound like? >> definitely the nausea and vomiting that's persistent suggests something that's actually being ingested that the body cannot handle. >> something ingested that the body can't handle? that's what linda's friend mary seibold thought all along. she said she shared her concerns with linda. >> let's have someone go into the house and just check it. let's see if there is anything foreign in here. >> but she says linda never took that advice. never had her home tested. now they all waited for the toxicology tests on linda's body. and sure enough, the lab that examined linda's samples did detect and identify something quite curious. linda curry's body contained lethal levels of nicotine, which only deepened the mystery because, according to everyone who knew her, linda curry did not smoke cigarettes or anything else. never had. >> never. never. >> did that make sense to you, nicotine poisoning? >> i had never heard of it. she never smoked. how could this happen? how could this be? no, i was shocked. i was shocked. >> is it unusual to find nicotine in someone's body? >> it's not unusual. we are exposed to nicotine either as a smoker or as a nonsmoker. >> there are more sources of nicotine than you think. besides cigarettes, there are actually small levels of nicotine in eggplant and potatoes. it also used to be an ingredient in insecticide. >> if you're working your garden and you were using an old insecticide that contained nicotine, you could possibly get it through absorption in the skin. >> enough to kill you? >> yes. >> in sufficient quantity, she says, nicotine is a deadly poison. >> in the beginning the individual may experience some nausea, vomiting. that's going to be followed with tremors leading to convulsions and complete respiratory depression leading to the death of the individual. >> you stop breathing? >> you stop breathing. >> that sounds like a very unpleasant way to die. >> yes. >> linda didn't garden either. and the coroner didn't believe that amount of nicotine got into her body by accident. so he classified her death as a homicide. you kept waiting for that investigation to go somewhere. >> exactly. >> never did? >> never did. >> detectives could not determine where the nicotine came from or how it got into linda's system. months passed, then years. linda's niece rikki ryecraft spoke with the lead detective and heard something that shocked her. >> he seemed to be inclined to think that she had committed suicide. >> that might have been the end of the story, were it not for this man, at the time a determined student. he never met linda curry, but one day he'd know everything about her. >> coming up. >> we went back through every interview with every witness. >> a new team makes a new discovery. when "dateline" continues. in 2006, when the name linda curry caught the eye of an orange county prosecutor named brahim batai, the case was as cold as it could be. linda curry was already dead by the time you even came to work here. >> linda curry was dead when i was in law school. >> nevertheless, batai and the sheriff's investigator decided to take another crack at solving the mystery more than a decade after linda's death. >> we went back through every interview that was conducted with every witness. >> they also went deep into linda's medical records and found out something very strange had happened during her first hospital stay. >> the nurse came back to the room and found the iv bag had a discolored fluid in it and changed it out. >> after that discovery she learned, linda became seriously ill, ending up in the i.c.u. eventually she got better and went home. but then four months later she was sick again, back in the hospital. and again. something odd occurred. >> at that hospital the iv, the port on the iv, which is where they do injections into an iv, was broken. >> this is a different hospital. >> different hospital, different staff. >> had someone tampered with those bags? could it have been poison? that was never clear. >> they tested everything. they couldn't tell. >> normal toxicology tests, normal hospital testing won't pickup nicotine unless you're looking for it? >> unless you're testing for it, correct. >> the incidents were as troubling as they were mysterious. no surveillance video or security tape showing anybody doing it. >> no. the only common denominator is linda and paul. >> so linda was getting the treatment and paul was right there by her side as a dutiful husband? >> yes. >> paul the dutiful coating husband, as they reviewed interviews and conducted new ones, they quickly picked up on a theme. linda's friends and family didn't much like him. her niece ricki. >> there was this arrogance about him. >> remember, paul was a physicist, a member of mnsa, a jeopardy winner, and a farntly apparently he didn't keep any of that a secret. >> he was on a social level we weren't and he looked down on us. >> he thought he was better than you? >> definitely. >> linda, of course, loved paul's intelligence and the way he spoiled her. but when linda got sick, her friend mary got suspicious. >> she was telling me, oh, paul is now making me these salads and making these dressings. you know, mary, he's such a good guy. he's drawing a bath for me after i eat making me soak, and she's getting soak. >> and you think the salads and the homemade dressing and the hot bath all has something to do with this? >> i think he's a nuclear physicist, yeah. he's msa. he's a smart guy. i think he was trying different things. >> things like nicotine? was that even possible? well, not impossible, according to toxicologist sabr jones. if you give somebody a spicy or savory enough dish, they might not notice there is a significant amount of nicotine in there? >> it would be possible. >> if you introduced it in someone's bath water and put in some perfume or scented soap of some kind? >> may be able to mask any odor that it may produce. >> so there's a lot of ways you can get nicotine into your system without noticing it. >> possible. >> it's worth remembering that paul got sick at the same time linda did. so whatever affected her seemed to affect him, too. but as friends and family watched paul get well, and linda get sicker, their suspicions hardened. you always immediately suspected paul of having done something. >> um-hmm, from the first phone call. >> i thought he definitely was trying to kill her. >> other people thought the same thing? >> absolutely. >> nobody called the police? >> there was no proof. >> still, mary says, she tried to warn linda. >> i told her she had to leave. >> and she'd say, what, you're seeing things? >> she'd say, mary, he's a good husband. he wouldn't hurt me. >> those worries from friends and family, the mystery illness, the questions about the ivs, a lot of suspicions, but no evidence, and certainly no witnesses, except one. linda curry herself and what she had to say was breath taking. >> coming up. >> how long have you been -- >> linda's powerful words from the past. >> if somebody were trying to do something to you, if they were trying to poison you, any idea who would try to do that? >> when "dateline" continues. has 4x more hydrating power than the $400 cream. for skin results you'll see, or your money back. olay. face anything. for even more hydration, try olay serums. car vending machines and buying a car 100% online.vented now we've created a brand new way for you to sell your car. whether it's a year old or a few years old, we want to buy your car. so go to carvana and enter your license plate, answer a few questions, and our techno-wizardry calculates your car's value and gives you a real offer in seconds. when you're ready, we'll come to you, pay you on the spot, and pick up your car. that's it. so ditch the old way of selling your car, and say hello to the new way-- at carvana. one of the worst things about a cois how it can make you feel. but, when used at the first sign, abreva can get you back to being you in just 2 and a half days. be kinder to yourself and tougher on your cold sores. robinwithout the commission fees. so, you can start investing today wherever you are - even hanging with your dog. so, what are you waiting for? download now and get your first stock on us. robinhood. in california, we're the only state where wealthy trust fund heirs get their own tax loophole. these tax cheats avoid millions in taxes on vacation homes and coastal mansions depriving our schools. prop 19 closes this unfair loophole that's been exploited by an elite few and helps our schools, firefighters, and seniors. vote 'yes' on prop 19. tell them [record scratch] the party's over. hello, i'm dara brown. here's what happens happening. the international space station is preparing to celebrate a milestone. monday will mark 20 years of continuous human presence on the international space station. 250 miles above earth. since expedition one first arrived at the iss, hundreds of engineers and astronauts have transformed our understanding of space. nasa is now publishing a collection of houston, we have a podcast, episodes about the international space station and its history. now back to "dateline." >> that's from -- >> as prosecutor batai and investigator looked into the decade old mystery of linda's death, they found something remarkable. two interviews with linda curry. turns out after strange things happened with linda's ivs while she was in the hospital, detectives had interviewed her. and those conversations were recorded. >> how have you been feeling since you left the hospital? >> i feel great. >> now investigator shoal put her headphones on and listened to linda curry's voice. >> she seemed to be joking about the apparent damage to the iv. but detectives weren't laughing. they knew linda's friends and family suspected paul. >> i was under the assumption now that paul is doing this. >> yes, something is being done. we knew something is being done. >> linda did acknowledge the suspicions of others. >> all of my friends are saying paul is guilty, get out of the house. >> but, she said, she did not suspect her husband. she described a loving partner who nursed her through her illness. and she seemed to mean it in that interview. but in another one she said something entirely different. so different it makes you sit up a little straighter. >> if somebody were trying to do something to you, if they were trying to poison you, any idea who would try to do that? >> well, the only person i could think of would have a motive to do it would be paul. the only motive i can think of is money. >> for investigator shoal, this was a revelation. she says it's why she stuck with this case for so many years. >> it's very rare to find a motive in a homicide at all. and in this case i had a motive. >> handed to you by the victim. >> yes. when i listened to that interview, i thought, this is a solvable case. >> you thought, she laid it out for us. we should finish it. >> property grave, we have to find justice. >> they began to follow the money. it turned out linda was worth a lot of it. she had retirement accounts at southern california edison, and almost $700,000 in life insurance. and despite her reluctance to believe that paul was trying to poison her, she had changed those insurance policies, making her sister pat, not paul, the beneficiary. according to prosecutor batai, paul only found that out after linda's death. and he wasn't happy. >> he had letters that he sent to all these insurance companies saying, we paid for the premium of these insurance companies from our marriage money. i'm entitled to it. >> shoal also found out that paul had filed an insurance claim for a lady's rolex watch and some jewelry that had gone missing after linda's funeral. he received a $9,000 payout. but investigator shoal knew that linda had wanted the rolex to go to her sister. >> and i called her and said, there's a report that the watch was stolen. she goes, no, i have the watch on right now. >> in fact, the watch had never been stolen. paul curry, it seemed, had filed a phony insurance claim. >> who does that? if somebody is an innocent spouse, grieving the death of his beloved wife, who decides within days after that to fake the theft of her rolex and file a claim to collect money? >> paul, apparently. but it turned out he needn't have bothered. shoal and batai learned that linda's conflicted feelings about paul ran deep. five months after taking him off her insurance policies, she wrote her sister pat a letter, a will, and left paul $400,000, which he eventually received after her death. but by then paul had other troubles. within a year of linda's death, paul's boss mike flower discovered that his star employee was not a nuclear physicist as he had claimed publicly and on his resume for so long. >> he didn't have a degree at all. paul ended up submitting his resignation. >> and if he had not, he would have been fired? >> yes. >> to lie about something that can be so easily checked, that says to me that the person doing that has an unbelievably large ego. >> it was very disappointing. >> somebody who thinks they can get away with anything? >> it was very disappointing. >> all of it added up to a deeply unflattering portrait of paul curry. but did it add up to a case for murder? prosecutor batai knew it did not. he and shoal faced exactly the same problem detectives had in 1994. lots of suspicion, but no direct evidence that paul killed linda. and batai felt their prime suspect, a self-proclaimed genius, knew that. >> he was smart enough to realize that any police officer, the minute after she's murdered, is going to expect the husband to be the suspect. he was one step ahead. >> batai's theory? paul tested different poisons, carefully picked an obscure one, then poisoned himself to cover his tracks. >> the first time linda got sick, he had the exact same symptoms because that allows him to say, hey, look, we both got sick. maybe we gboth got something. >> you think that'sing? >> that's his m.o. >> he went back to the night linda died and the nicotine that killed her. he consulted a nicotine expert who looked at the case back in 1994. >> he goes, yeah, i remember the case. nobody ever followed up with me. i go, would you kindly, please, be willing to write a report to us about your interpretation of the result? >> it turned out to be the breakthrough batai needed. the amount of nicotine in linda's blood was extraordinarily high, nearly 100 times what you'd find in a regular smoker. forensics toxicologist sabra botch-jones. >> for the amount it would take it was above the limit. >> paul maintained he was with linda hours before she died. >> that allowed us to say it is absolutely categorically no other human being that had the opportunity to do what he did. >> prosecutor batai and investigator shoal knew it was now time for some show and tell with paul curry. >> coming up. >> paul curry had something to reveal. >> i have been less than honest about that. >> when "dateline" continues. es skip to cold relief fast with alka seltzer plus severe powerfast fizz. dissolves quickly. instantly ready to start working. ♪ oh, what a relief it is! so fast! another bundle in the books. got to hand it to you, jamie. your knowledge of victorian architecture really paid off this time. nah, just got lucky. so did the thompsons. that faulty wiring could've cost them a lot more than the mudroom. thankfully they bundled their motorcycle with their home and auto. they're protected 24/7. mm. what do you say? 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>> first she confronted paul with the phony insurance claim on linda's watch. >> i've been less than honest about that and, um, quite frankly it just was a poor decision. >> so right there in that room, he's basically copping to insurance fraud. >> yes. >> which is way less serious than murder, but -- >> but it's still a crime. >> but when it came to linda's death, paul seemed like a man with nothing to hide. in fact, he was the one who brought up the incidence with the ivs. >> something went on in one of her hospital rooms. it was never really explained to me exactly what occurred. >> school wanted an explanation, too, but first she wanted a reaction. she played linda's 1993 interview with detectives for paul. >> the only person i could think of that would have a motive to do it would be paul. >> paul, do you have any comments? >> unusual to hear her voice. >> unusual to hear her voice? >> it's nostalgic. >> it was nostalgic to hear her voice? >> yes. >> he's a cool customer. >> yes. >> but now it was time to ask the biggest question of all. >> did you kill linda? >> absolutely not. i loved her dearly. >> would you have a reason to kill linda? >> absolutely not. it's an open mystery. i mean, it's an unsolved death, but -- >> right, but part of it is not unsolved. we know what killed linda. we know that it was nicotine. >> right. >> and now you show him the report saying she had to die within two hours of getting the nicotine. >> right. >> i don't know how to respond to that. >> the man who had always had all the answers suddenly had none. >> i'm kind of taken by surprise. you're drudging up memories that are uncomfortable. >> he still he's he's going he still thinks he's going to walk out of that interview? >> he does. >> he miss calculated. school knew if paul didn't change his story about being alone with linda the night he died, he was essential lip admitting that he and no one else had the opportunity to kill her based on that expert's report. two hours in, yvon left the room to cauley bra him baytieh in orange county to let him know how things were going. listen to what paul says to the other detective as he weights for yvon to come back. >> should i presume i'm not going to make my 4:00 meeting today? >> and he wasn't joking. he was serious. because in his mind he's thinking, maybe they're suspicious of me. they don't have enough to charge me. that was his mistake. >> because he never made that meeting. >> he never made that meeting. >> 16 years after linda curry died. >> i am placing you under arrest for the murder of linda curry. >> yvon school handcuffed paul curry. >> am i allowed to call anybody? >> not right now. >> the man linda loved, married and trusted. linda's best friend mary seibold heard the news in can have. >> i'm sitting there and all of a sudden i'm seeing paul curry's mugshot. look, there's paul. >> what this man did is for about eight, nine months, he was poisoning her. he was watching the impact of what he was doing on her every day while at the same time holding her hand and saying, i love you, honey, i'm here for you, honey. >> you're describing an elaborate con that ended up being kind of a murder in slow motion. >> yeah, elaborate, diabolical. >> paul curry entered a plea of not guilty. prosecutor ebrahim baytieh knew it would be a tough case. there was no physical evidence tying paul to linda's death. and paul's defense attorney had a very different theory about how that nicotine got into linda's system. a theory that hinged on a stunning question. could linda have poisoned herself? coming up. >> she was very, very desperate to find a cure. >> what other secrets would tumble out in court? >> i go upstairs to the extra bedroom and i'm going, oh, my gosh. >> when "dateline" continues. it's a buick. it's an alexa. check it out. alexa, turn on the outdoor lights. ok. that's cool, but i'm pretty sure it's a buick. clearly an alexa. alexa, get directions to the 8-18 grill. getting directions. it's a buick. the first-ever encore gx, available with alexa built-in. nice buick. it's an alexa. now get nearly 3,300 purchase cash on the 2020 encore gx. ask: alexa, tell me about buick suv's your happy place. find your breaking point. then break it. every emergen-c gives you a potent blend of nutrients so you can emerge your best with emergen-c. ojust one jar of olay retinol24? hydrates better than the $100 retinol cream. for smooth, bright skin or your money back. olay. face anything. and try new retinol24 max. but she wanted someone who loves with the cats.ng. so, we got griswalda. dinner's almost ready. but one thing we could both agree on was getting geico to help with our renters insurance. yeah, switching and saving was really easy! drink it all up. good! could have used a little salt. visit geico.com and see how easy saving on renters insurance can be. september 2014, 20 years after linda's death, and four years after paul's arrest, it was finally time for him to face a jury. his defense attorney, lisa coppell man, argued that the prosecution's case was all a caldron of suspicion stirred by linda's friends. >> they tell the doctors their suspicions. they tell -- they talk to each other about their suspicions over the years. so everything starts getting interpreted in suspicious ways. >> suspicion without evidence, said coppellman. there was no evidence paul had ever bought nicotine or any other poison, nothing to tie him directly to linda's death. on the contrary, according to coppellman, paul was a loving, caring husband. she called paul's friend steve whitley to testify. >> she wasn't in a harmful environment to my knowledge, anything i saw. >> it never occurred to you that paul might have had any evil intention toward his wife? >> no, no. there was just -- just didn't see it. >> so how did linda get a lethal dose of nicotine? the defense had a bombshell theory, that linda herself was responsible. >> because she had been very, very sick and was very, very desperate to find a cure. >> coppellman explained to the jury that nicotine was sometimes used as a homeopathic cure to treat illnesses with symptoms similar to linda's. >> when we go to mexico, they would sometimes pickup herbs. >> steve said he couldn't remember what the herbs were, but to the defense it meant that linda was willing to try anything. maybe even nicotine. >> and in light of the type of illness that she had and her tendency to use herbal medicine and nontraditional medicine, it's very reasonable to think that she took steps -- and this is not a drastic step. >> maybe it was only accidentally drastic, an inadvertent overdose that caused an unintentional suicide. so the defense argued. prosecutor ebrahim baytieh said this was no accident. it was a premeditated plot by paul curry. >> he married her, planning on collecting on all the life insurance. he murdered her. by poisoning her. and he collected on the life insurance. >> the jury heard from linda's best friend mary seibold who stayed at their san clemente home while linda was in the hospital. >> i go upstairs to the extra bedroom, and there laying out on the bureau are all of her documents. her 401(k), her life insurance. >> so somebody is looking through her insurance, her 401(k). >> right. >> all the stuff you would go through if somebody was dead. >> exactly. >> that somebody was paul, said the prosecutor. and remember that email that paul sent mary the morning of linda's death? the one asking for mary's help? >> he says, i'm worried about linda. i'm worried something bad's going to really happen to her. >> this is how many hours before linda died? >> 16 hours before. >> you think paul is laying the groundwork there? >> absolutely that's what it is. >> baytieh revealed to the jury how he believed paltrow deuced that fatal dose of nicotine into linda's system. during the autopsy, the medical examiner found an injection mark behind linda's ear. >> you think he stuck a needle in her? >> no doubt in my mind that's exactly what he did. >> and you think he's getting, what, frustrated? >> yeah. it's time to cash this paycheck. >> and while there is no evidence paul ever bought nicotine, baytieh said he didn't have to. he could have distilled it from cigarettes. >> right. >> he would have known how. >> it's very easy. >> the prosecutor had one more surprising revelation for the jury. he called leslie curry to testify. she was paul's wife prior to his marriage to linda. leslie told the jury that over the course of several months during her marriage to paul, she became very weak and sick. when paul told her to get life insurance, she took the required blood test, but the insurance company declined coverage. and after that, leslie said, two things happened. paul left her. and she got better. >> do you think paul poisoned leslie? >> i think he was poisoning her, yes. and i think if she would have got the life insurance policy that he would have killed her. >> the prosecutor had one last opportunity to convince the jury to convict paul curry. the mnsa member and former jeopardy contestant of murder. and in his closing argument, he channelled alex trebek. >> category, human criminality. book smarts. greedy. arrogant. insatiable appetite for money. sneaky and manipulative. got away with murder for 16 years. who is paul marshall curry? >> after three weeks and more than 30 witnesses, the jury had the case. and the next day they reached a verdict. >> we the jury in the above entitled action find the defendant paul curry guilty of the crime of felony -- >> guilty of first degree murder, sentenced to life in prison with no possibility of parole. the jury had reached a verdict on how linda died, but there was still one lingering question. she was smart. she was educated. she had a good job. she couldn't wacould have walke out the door at any time if she thought she was in danger. >> that was the hook. he said, i love you. i will be here for you. he held her hand. he preyed on her. >> look, we all want somebody in our lives who loves us and tells us how great we are. linda curry not alone in that, but how long are you willing to stick around for what turns out to be your eventual murder after you already suspect your husband? >> in linda's case, for the rest of her life. >> that's all for this edition of "dateline." i'm craig melvin. thank you for watching. >> i'm craig melvin. >> and i'm natalie morales. >> and this is "dateline." >> my whole family is just heartbroken. we're all shells of people walking around. the happiness in our life has been taken from us. >> they were high school sweethearts rearing five strapping sons. >> it was a rowdy house, and our parents loved it. >> then that terrible night. >> she's got blood everywhere, everywhere.