"Murder for hire" returns with David Muir. Reporter: Across the Hudson river from New York City, the part of New Jersey known for neon and noir. The version of Jersey made famous by "The sopranos" and... See More
"Murder for hire" returns with David Muir. Reporter: Across the Hudson river from New York City, the part of New Jersey known for neon and noir. The version of Jersey made famous by "The sopranos" and the mob boss who called the shots. But the plot we're tracking tonight is about to play out in broad daylight with a much different boss calling the shots. Right there on surveillance -- that's Nicole faccenda, a suburban soccer mom, and a scorned lover. Sitting in a supermarket parking lot, unsuspecting shoppers pushing their carts right past her. So she's doing a little shopping, and then she's comes out to meet with the hit man. Yes. Reporter: Because that's what most people have on their grocery list? She did. Reporter: Shopping for flowers, she says, but cops believe she's in the market for murder. Hi, how are you? Have a seat. Okay, how are you? Reporter: Plotting revenge on the other woman. So what can get done? You can just make her disappear? You could -- what could get done? When you, all right, when you say disappear, like, you want her out of this State or you want her, you know -- Basically you're saying you could just go break her legs or you could go -- Exactly. Do anything? Reporter: And who is she trying to hire? You'll remember our hit men who are, in fact, undercover federal agents, who've agreed to it down with us as a group for the first time ever. But to do it, they spend hours getting disguised, among them an agent we're calling Jose. Covered in a sort of goo before as he gets a brand-new appearance. They make a mold. And from there, they build new features for his new face. The same agent who would sit in that car with that scorned lover. I don't want to keep beating around the bush. Reporter: And it turns out, it's not just her first time. This is his first time as a hit man. And he takes us to where it all began, we rigged the car to avoid showing his face. How did she get to this point where she wanted to kill another woman? She was angered at the fact that he was leaving her, and she wanted her dead because she wanted to get back at him. Reporter: Nicole's bad breakup, smiling here with that limo driver boyfriend, but that boyfriend with a double life. A few exits down the parkway, he has another girlfriend named Jennifer, a nurse. And it turns out another family. Two children with her. She's just a Who's been involved -- I think she's like 30 years old. She's got two kids there. You don't want to hear the whole . Reporter: But she wants the boyfriend to live? She wants him to live because she wants him to grieve. Reporter: She wants to watch him suffer? Yes. Reporter: Nicole in the lonesome corner of a love triangle. And nobody puts Nicole in a corner. A little grocery shopping, a little homicide, just the cure for a broken heart. I've played every scenario through my head a million times. Do I want the car to go off the highway? Do I want someone to just come up and take her out? Do I want me to go into the house with my silencer and take them all out? Like, I go to sleep every night thinking of these things. Reporter: She goes to sleep at night, wrestling with how to murder the other woman. But wide awake, just a few cars away in that supermarket parking lot, federal agents listening to her every word. Among them, agent Angela Mullins. So she has no idea that as she's talking to the hit man you're right here in the same parking lot, listening to the whole thing. No clue. Reporter: And what are you listening for? To show that she wants to carry this through. Reporter: So you're listening to make sure she really wants to kill this guy? Absolutely. Reporter: For days, every secret meeting, every phone call, every text message intercepted, and all of it given exclusively to "20/20." So the whole time there are shoppers in the parking lot, and there's a murder being planned. She's plotting to kill someone. Reporter: Murder for hire in America? On your lunch break. Reporter: But nothing in that car is what it seems. The guy in the backseat right there, he is the man who introduces Nicole to the hit man. So she's thinking of the darkest person in her life, the person who might know a hit man out there. Yes. Reporter: Ironically, the guy she relies on for help is a relative of her ex-boyfriend. And she asks him what? She asks him if he knew someone that is willing to kill someone for her. Reporter: He knows right where to find her a hit man, because what she doesn't know is that he's long been an undercover informant for the feds. You just tell him the scenario and he'll get it done, no , que sera sera. Reporter: What's going through your mind when the person across from you wants someone killed? You just wanted to yell at her, "What's wrong with you? And you, you have to sit there with your poker face. And, "Okay, if this is what you want done, this is what I'm going to do." Reporter: Suddenly the first test for that first time hit man. She thinks he looks more like a cop than a killer. She told me I didn't look like a hit man. So my question to her was "What's a hit man look like?" Reporter: You look like one today. Yeah. Today I do. Reporter: On the other hand, Jose says, Nicole doesn't look much like the usual suspect either. Nicole appearing very nervous. Leaning far away from Jose, only her hand in view at this point, and Jose tries to reassure her. Okay. Scott said you had a problem with somebody and I'm here to take care of your problem, but what is it you want me to do with your problem? Okay. I don't know. Fix my problem, I guess. How do I fix your problem? You tell me what you want me to do and I can see to it that it gets taken care of, but -- Reporter: And watch right here as Jose is about to be interrupted, soon looking down at his phone. She's going to do something to you, so you want to do something to her in return? Reporter: He's Reading a text, and it's actually help from those agents listening from a nearby car, now coaching him. But listen to how he explained it to that suburban soccer mom, saying it's just his friends texting. Asking to go out for beer. We listen in as Jose goes down his mental checklist -- right here offering the standard hit man disclaimer, her out. You've got to be serious about this Too. You know what I mean? Because once it's done, it's done. There's no turning back. You understand that. Reporter: And while Nicole may be new to this life of crime, she's a quick study. Because as it turns out, she's seen a lot of TV. I just want to make sure you're not like an undercover or a federal agent. Okay. And like all of a sudden, cars are all over. If I get arrested, I'm -- I'll lose my job. Reporter: And just listen to what she says next, fearing she's a star in the making. And I know I've watched one too many lifetimes. I'm in a horrible, horrible -- Lifetime? I've watched too many lifetime movies. This is about TV now? Reporter: So she says to you she feels like she's living a lifetime movie? Yes. Reporter: Now she's living a "20/20." Are you worried this thing could go down the tubes because she is so suspicious? She's looking around, looking for cameras, and at first that is a little bit unsettling. Reporter: And Nicole is not only suspicious, in that supermarket parking lot, she demands a price check. And so do you have like a price list? If you want her dead, it's going to be five up front and five at the end once it's completed. That's it, ten? Yeah, give me ten. She thought my price was too low. Reporter: She thought you were a cheap hit man? Yes, she actually did. She raised the money. It was funny. Reporter: You guys got to talk about your rates -- I know, really. Reporter: Watch as Nicole leaves the car with a smile on her face, laughing, after the deal she got at the supermarket.
This transcript has been automatically generated and may not be 100% accurate.