After nearly three years, thousands of man-hours of official and unofficial investigations and virtually unprecedented international media attention, it took a pot-smoking poker player to wring damning admissions from Joran van der Sloot about the disappearance of Natalee Holloway from an Aruban beach in the spring of 2005.
ABC News has obtained exclusive U.S. rights to this stunning new information caught on tape and will air a 90-minute special edition of "20/20: The Final Hours of Natalee Holloway" Monday at 9:30 p.m. ET.
In an exclusive interview with ABC News, Patrick van der Eem, 34, described in detail how he painstakingly gained the young Dutch suspect's trust, took his suspicions to Holland's leading investigative reporter and began a sting operation that led to van der Sloot's caught-on-camera admissions that he panicked when Holloway had what he describes as a seizure during a sexual encounter and called a friend who came and took the body out to sea.
After he said he spent two months almost constantly with van der Sloot -- building the younger man's trust one joint at a time -- van der Eem said he went to Dutch crime reporter Peter R. de Vries and offered his services. De Vries, who is known in Holland for tackling complex cold cases by sometimes unorthodox means, hired van der Eem and set him up with a brand new Range Rover equipped with three hidden cameras, audio recording devices and a GPS-like tracking system, and the sting began in earnest.
If the taped conversations are accurate, it appears that Natalee Holloway could have been alive when her body was apparently dumped about two kilometers off the coast of Aruba by a "good friend'' of van der Sloot.
Still, it remains unclear whether the new evidence will be sufficient to bring any charges against van der Sloot, Aruban attorneys told ABC News, and the case could remain technically unsolved indefinitely. Aruban prosecutors have said they will wait to gather all the information before deciding on whether to bring new charges.
Van der Sloot on Friday insisted insisted in a phone call to a Dutch television show that he was lying when he described the night Holloway disappeared to van der Eem; that he was telling him "what he wanted to hear.''
"It's easy to prove that what I said is not true, and that actually this is much ado about nothing," he said on the Dutch current affairs program.
Van der Sloot attorney Joe Tacopina told ABC News that his client's statements "are not a confession."
"As a matter of fact Joran denies any role in Natalee's death,'' Tacopina said. "It is important to point out that the prosecutor has viewed this tape over one week ago and Joran is at liberty. I think it speaks volumes about the evidentiary value of this tape considering he has been arrested previously in this case with little evidence against him."
But the sheer detail that Van der Sloot goes into on the recorded tapes and the seeming camaraderie between the pair over hours and hours of tapes raises questions about why someone who has steadfastly and for so long denied any involvement in the Alabama teen's disappearance would suddenly change course and make up such a detailed version of the events of that fateful night.
The entire operation began by chance in a Dutch casino. Van der Eem, a bold and emotional Dutch businessman who had never met van der Sloot before but followed the case with a passion, ran into his eventual target and claimed he decided on the spot to try and get inside the head of a man he believed had disgraced their nation.
"Getting involved is hard, you know, but I knew if I could have done something, or can do in the future, I will," he said.
"And when you saw him in the casino,'' ABC News' Chris Cuomo asked him, "you said this is your chance?"
"And I will finish him,'' van der Eem replied, explaining that he'd grown frustrated watching van der Sloot tell one news organization after another that the Aruban people are "with'' him.
"The Aruban people are good people who will give you the trust, because the justice system sometimes fails a little bit. But I knew there was something wrong in this story,'' van der Eem said.
Van der Eem adopted a strategic approach.
He walked up to van der Sloot and said without introduction, "Hey murderer'' in Papiamento, the official language of Aruba.
He said he knew that "nobody on the other table would understand what I said to him because we live here in Holland and … we talk Dutch.''
After getting van der Sloot's attention, van der Eem said, "I went, 'How are you doing? Fine?' And I walked away. I went smoking a cigarette. And two minutes later he came [over].''
Van der Eem struck up a conversation with van der Sloot and began asking him how he spent his summer. The young man replied that he played poker and smoked marijuana, van der Eem said, and the "game was started."
Like a seasoned undercover agent, van der Eem began to identify his target's weak spots and exploit them as best he could.
"Playing poker, OK, that's one addiction. And smoking weed every day, that's-- OK, I'm going to hit on that one,'' Van der Eem said.
"I asked him how much he paid for a gram of weed. He told me 70 Euro. I told him, 'Are you crazy? I'll give you my number. And I'll help you with 100 grams [for] 300 Euro.' He told me, 'Yeah, man, that's good.' It took exactly two days for him to call. And as soon as he made that call, I knew what I was going to do with him."
Van der Eem said that "the game was started with saying, 'matung.'
"And then it proceeds.''
Van der Eem said he spent nearly every day for two months with van der Sloot. The pair smoked marijuana, drove around Holland and played poker late into the night, van der Eem said.
The next step, he said, was holding van der Sloot's interest. He suggested that they monetize their common interest in marijuana by growing and selling pot in the Netherlands.
"We got to start something up, '' van der Eem said he told van der Sloot. "Let's go green!
"He loved it. Oh, he was enjoying it."
So, after months of priming his target, he said he went to de Vries.
"He came to me and said, 'Joran is trusting me completely,'' de Vries told ABC News. 'And I think he knows more about [the Holloway disappearance] and he will finally tell me. Are you interested?' And I said, 'Of course I'm interested. Stay as close to him as you can because this can be very important.' And well, that's what he did.''
Van der Eem said he gained the other man's trust slowly, by playing the role of a criminal and repeatedly telling van der Sloot that he didn't care about the case.
"I don't care. Let's play poker. I mean, let's play a game and let's go have some fun,'' van der Eem said he told van der Sloot whenever the young man brought up the case.
De Vries said van der Eem set a good trap for van der Sloot.
"Joran was a little bit amazed [by van der Eem] … because most people meeting Joran will ask in already 10 minutes, 'Well, tell me, did you do it or not?' But Patrick was not interested at all.''
But at the same time, van der Eem said he tried to re-enforce the underworld ethic of silence at all costs, saying, "Never talk, never talk. … We don't talk! It's going to be you and me. We trust each other and we never talk to anybody."
But once the trap was set -- once de Vries had set van der Eem up with a brand new Range Rover tricked out with three hidden cameras, audio recording devices and a Lowjack-like tracking system, de Vries and van der Eem learned that their target had been re-arrested and was back in custody of the Aruba authorities.
"Three days before I was getting my car, he was gone,'' van der Eem said. "Oh, and it was the most … pain in my life. Peter [de Vries], me…everybody was devastated."
But the arrest eventually worked in their favor: Once a judge ordered van der Sloot released for lack of evidence and prosecutors acknowledged they would close the case, van der Eem said he realized he had a new opportunity on his hands.
Van der Sloot, whose cell phone had been confiscated by Aruban authorities, located van der Eem through a friend.
"It was over," van der Eem said. "That's what I'm telling him. 'Wonderful, man! Now we're going to make money [growing marijuana]."
As the pair sat in the Range Rover back in Holland, van der Sloot began to open up about the case, van der Eem said, acknowledging for the first time that "they'll never find'' Holloway.
What followed in the subsequent days inside the Range Rover, van der Eem said, confirmed all of his suspicions.
Confident that he could "never be nailed for this again,'' van der Sloot began to speak disparagingly of Holloway and even bragged that he went home that night, established an alibi by e-mailing friends and then fell asleep, according to the undercover tapes and interviews with van der Eem and Dutch journalist de Vries.
After his release in December and the Aruban prosecutors' admission that they couldn't build a strong enough case to convict him, van der Sloot spoke crudely about Aruban authorities and said he was expecting a "big fat compensation check … for the ... damages'' as a result of a civil complaint -- a "really big fat one'' that he said on tape he planned to use to "buy a little house in Spain."
Van der Sloot's admissions on the tapes came slowly, over the course of several days in January, according to de Vries and van der Eem.
"I know what happened to that girl,'' van der Sloot told van der Eem at one point, in the first solid admission he makes.
"She's dead, isn't she?" van der Eem asked.
"Of course,'' van der Sloot replied, coolly.
He went on to say that he was "just incredibly lucky that she's never been found. Because if they found that girl, I'd be in deep [excrement]."
Van der Sloot said that the seizure occurred during a romantic encounter between the pair, who had just met up hours before at a local nightclub.
"Suddenly, she wasn't moving anymore,'' van der Sloot said.
At another point, he told van der Eem, "I tried to shake her. … I was shaking the bitch. I was like, 'What is wrong with you man?' I almost wanted to cry.
"Why does this s*** have to happen to me?" he asked.
In a voice seemingly devoid of emotion, van der Sloot said he turned to a friend of his.
"So I went and called the guy," he said. "I didn't call him on my cell. I walked over to a pay phone and I called him. And I told him, 'Well, this is what happened. Come, come, come help me. And please don't call the police.' He says, 'No I won't call the police. I'm coming to you now. And, he came there."
Asked how he knew Holloway was dead, van der Sloot said he "just knew it."
Van der Sloot said that he had known the unnamed friend since childhood and that "if I can ever do anything for him … I'd give my life for him.''
He went on to say that he'd take the man's name "to my grave,'' but a couple of days later identified him by his first name -- Daury.
After several conversations over a number of days, in which van der Sloot repeatedly talks about Holloway's disappearance, he told van der Eem, "It's a relief, really. … I've never told anyone [what happened to Holloway] in my life."
Finally, he insisted to van der Eem, "I'm putting it away and for me it's finished. Case closed."
When van der Eem replied that "you've got it off your chest'' and "it'll be alright man,'' van der Sloot turned to van der Eem and told him, "I'm being honest with you, Patrick.
"The two people I most trust in this … more than anyone, are that person and you."
Van der Eem, who grew up in the Antilles, said he decided to try to gain van der Sloot's trust out of anger that the young man's alleged crime had done so much damage to the reputation of the island of Aruba and the Netherlands. He said he combined his passion for information about the case with a false bravado to gain the trust of a man he believed carried a dark secret.
But in truth, he said, he was dying inside. At several points during his interview with ABC News, van der Eem became visibly distraught.
When Dutch prosecutors released van der Sloot in December and announced they had essentially closed the case for lack of evidence, van der Eem said he thought it was time to step up his own personal investigation.
It wasn't until that point that van der Eem said he felt close enough to van der Sloot to begin questioning him about the Holloway disappearance.
"The case is closed,'' van der Eem said he told van der Sloot, "and now, you know, if you want to tell me something, and, you know, I don't mind anymore."
"You know how much hurt I had saying those words -- 'I don't mind'?" van der Eem told ABC News, growing emotional.
"I definitely DO mind,'' he said.
"Why did I want this? It's obvious. Everybody was looking for the truth for [Holloway's] mother,'' he said. "I'm a father. I have two children, a girl six years old and a boy two years old."
He said there were times when he almost lost control of his emotions as he coolly played the part of a criminal.
"You know, I felt sometimes I had to cry, but I had to keep it in, you know? But as soon as he['d] get out of my car, my tears were coming."
Van der Eem said he never once felt he was betraying van der Sloot.
"No!'' he insisted adamantly to ABC News. "YOU betrayed MY country, and YOU betrayed the whole world, Joran. This is YOUR punishment."
Van der Eem said he found it painfully ironic that van der Sloot was able to go home and fall asleep the night he allegedly arranged for Holloway's body to be disposed of, since he said he himself had trouble sleeping.
"I had a lot of days I couldn't even sleep! And I was harming nobody. But with the information I had in my head? … Now, the release comes … my head is going to get empty talking to you, showing the world what happened."
Van der Eem said that throughout his investigation, his concern was less with gathering legally-admissible evidence than with cracking the case, for Holloway's family and for the Dutch and Aruban people.
"We're going to punish him,'' van der Eem said. "His punishment will be very simple, sir. He's gonna get a lifetime sentence. Maybe not in jail. But I would not want to be Joran van der Sloot after everybody in the world sees these" undercover tapes. … There ain't no rock in this world you can crawl under."
Van der Eem said he doesn't regret halting the investigation and not trying to take it any further than he and de Vries did. He said he did all he could, emotionally, and that he was leaving his undercover persona behind and getting on with his life.
"You said it's like a chess game,'' Cuomo asked him.
"Absolutely,'' van der Eem replied. "But I'm finished. It's checkmate."
For Holloway's mother, Beth Twitty, the new information is both a blessing and a curse, she told ABC News.
"It's over,'' she told ABC News. "I mean it. It's the end … this is the end for me. It's what I have prayed for for two and half years. I've just prayed for an answer, and that's all I've ever wanted. I've just wanted an answer to what happened."
Still, she said, "it makes you sick.
"How can [an individual] have such disregard or disrespect for a person's another person's life … and only be concerned about your own existence."
Later in the interview, she said, "Dear God! Joran could have called, he could have called an ambulance. He's not an EMT [emergency medical technician]. He's not a, a doctor! You know? He's not a, he's not anyone that could, could make a decision on my daughter's condition.
"And he chose to be that person himself, to decide, you know, whether he's going to seek medical help for Natalee with her laying there in his presence -- or is he gonna make the decision to dispose of her body? I mean, dear God! He did! And even though he didn't know if she was alive or not … dear God."
De Vries, the crime reporter, took his information to Aruban prosecutors last week and almost immediately, authorities on the island announced a reopening of the investigation, which just last month they had said would be closed due to lack of evidence.
"The office of the Public Prosecutor of Aruba has intensified its investigation of the case of Natalee Holloway due to recently received information,'' a press released issued last Thursday said. "This information may shed a new light on the mode of which Natalee Holloway has died and the method by which her body disappeared. … The Aruban Police Corps has continued the investigation of the case despite the formal discontinuation of the prosecution of the suspects of the day, in December 2007.''
As part of deal with defense attorneys for van der Sloot and two other local men, prosecutors had said they would discontinue the nearly three-year investigation by year's end if they couldn't gather enough evidence to bring a case.
The transcripts of van der Sloot's conversations with van der Eem appear to exonerate Deepak and Satish Kalpoe, two Surinamese men who live on the island with their parents.
Neither of the brothers could be reached on Sunday. A man who answered Satish Kalpoe's cell phone and said he was Satish's father declined comment, as did a woman who answered Deepak's cell phone.
Despite what appears to be damning new evidence, Aruban attorneys say that prosecutors still face an uphill battle in prosecuting van der Sloot, even if the tapes were ruled admissible in court.
ABC News' Andrea Beaumont contributed to this report.