Transcript for Model records exchange with Weinstein: 'Why yesterday you touch my breast?': Part 4
Reporter: Exterior shot night a New York police precinct the year, 2015. A young woman walks into the precinct's front door with a harrowing tale of sexual assault. And the police noticed that, first of all, she was upset. And they thought she was distraught. Reporter: The person who the shaken woman told police had assaulted her was none other than movie mogul Harvey Weinstein. I'm told they found her completely believable. You gotta remember, they're new York people. They know who Harvey Weinstein is. And they knew this was a significant allegation against a significant guy. Reporter: Columnist Michael Daly of the daily beast spoke to police sources who worked the case and compiled a blow by blow scenario of the woman's alleged encounter with Weinstein. She first met him on Thursday, radio city. Reporter: Act 1 of this drama unfolds on March 26, 2015 at the premiere of the spring spectacular show produced by Weinstein. Here he crosses paths with 22-year-old ambra Gutierrez a beautiful model from Italy. And he says, "Come down. We'll talk to you about, you know, your future in the business." And so, why not? Reporter: The very next day, the location shifts to Manhattan's tribeca neighborhood as Gutierrez walks into Weinstein's offices for that scheduled meeting. His assistant shows her in, I'm told, so she's got no reason to worry, right? Then the assistant steps out of the room, and she's there with him. And the story that she will later say is that he asked her if her breasts were real, and they felt them without her consent, and then tried to grope her under her skirt. Reporter: Police say the shaken Gutierrez leaves the building and goes directly to a friend who then takes her to that NYPD precinct house. The special victims unit is called in. They know this is not "He said, she said." This is a "He said, she said." But she is very convincing. So in their minds that makes her like this. Reporter: Then in a major plot twist, even as she's talking to detectives her phone rings it's Harvey Weinstein. He talks to her on the phone about, "Well, maybe come tomorrow night." And then the cops, they urged her to go and meet with him. And she agrees to meet him. Reporter: Cut to the following night the location a chic soho hotel. Gutierrez walks in and heads to the bar for the meeting with Weinstein in an undercover sting straight out of one his movies. They set themselves up so they can keep an eye on her. And they're recording the conversation with two cellphones, one of which is her phone. He offers her a drink, she says she's drinking water. She takes a picture and puts it on Instagram of the water glass. That's like saying, "I was not drunk. I was not drinking." Reporter: Under the watchful eye of police officers Gutierrez goes with Weinstein upstairs to his room but stops in the hallway outside his door. Ronan farrow was able to obtain a copy of the undercover recording. I'm telling you right now, get in here. What do we have to do here? Nothing! I'm gonna take a shower, you sit there and have a drink. Water. I don't drink. Then have a glass of water. No I don't want to. Honey, don't have a fight with me in the hallway. It's not nothing, it's -- Please. I am not gonna do anything, I swear on my children. Please come in. On everything, I'm a famous guy. I'm, I'm feeling very uncomfortable right now. Please come in now. Reporter: Now listen closely as Gutierrez confronts Weinstein about his alleged groping of her the previous day. Why yesterday you touch my breast? Oh please, I'm sorry, just come on I'm used to that. Come on, please. You're used to that? Yes, come in. No, but I'm not used to that. I won't do it again, come on, sit here. Sit here for a minute, please? No I don't want to. This is a man admitting to a sexual assault and also describing it as a pattern of behavior. Pretty chilling and disturbing. But also it's disturbing audio to hear, you know, this is a woman saying, "No," again and again and again that she doesn't want to go into this room and, you know, it appears this is a man who does not, want to take no for an answer. I will never do another thing to you. Five minutes. Don't ruin your friendship with me for five minutes. I know, but it's kind of like, it's too much for me, I can't. Please you're making a big scene here, please. No but I wanna leave. Ok bye. Thank you. Reporter: Police have heard enough they confront Weinstein and bring him into the station for questioning. News of the incident quickly becomes public but curiously lurid articles about his accuser soon begin popping up in the tabloids. The New York post reports that Gutierrez had asked Weinstein for a film role after the alleged incident and that as a Teager she had accused her older, wealthy boyfriend of sexual assault. Other tabloids go to town with details of how Gutierrez had attended one of former Italian prime minister Silvio berlusconi's notorious sex parties. It's my opinion, that his high-powered team started putting out stories about my client that would have weakened her, would have emotionally impacted her, would have caused her to recoil. And sure enough heller says Gutierrez soon stops cooperating with authorities. She eventually reaches a financial settlement with Weinstein, signs a non- disclosure agreement and leaves the country. When you have the ability to be compensated with a lot of money, and on the other hand, you say, "Oh my god," if you're a victim, "All my history is gonna come up," I don't blame her at all, I understand it. But remember, even without Gutierrez's cooperation prosecutors still have that audio recording of Weinstein seemingly admitting to sexual assault. They routinely lock up, prosecute and convict and jail subway gropers on a lot less evidence than that. Reporter: But in the end the district attorney drops the case against Weinstein saying his prosecutors just didn't have enough evidence to convict. I, like they, were very disturbed by the contents of the tape. Our sex crimes prosecutors made a determination that this was not gonna be a provable case. I don't think that it should have been any reluctance on the part of the district attorney. There would've been two years of victims that might have been spared the anguish of going through what we see coming out of the woodwork now.
This transcript has been automatically generated and may not be 100% accurate.