Reporter: They dissolve quickly and leave no smell, no taste and no trace. Date rape drugs. Surveys show roughly one in five students is sexually assaulted while in college. In fact, even the... See More
Reporter: They dissolve quickly and leave no smell, no taste and no trace. Date rape drugs. Surveys show roughly one in five students is sexually assaulted while in college. In fact, even the president is calling for action. Some of this is a job for government. But really, it's up to all of us to be brave enough to stand up and help put an end to these crimes. Reporter: So we set up a scenario at the mason jar in mahwah, New Jersey. Saw you around campus. Yeah. Reporter: A young, female student is approached by two classmates. I think I'm going to go the bathroom, actually. Reporter: She's about to become a victim of predators with dark intentions. What would you do if you saw this? Hey. Hi. What's up? Hey. So, you come here often? Ah no, actually, this is my first time around here, so. What does that say? Don't study -- Yeah, that's what it says. Reporter: Within seconds, these young college girls put the guys on their radar. What class is that? Government. I think I took that class. Did you? Yeah. Do you want to come over here? The plan is to not study. Okay, one glass of red wine, that's it. And I need to study. Okay? I'm going to go the bathroom. Reporter: While she's away -- All right, do it. That's fine. I'm going to do it. Dude, dude, not cool. Not cool. It's flu medication. No. No. Hey! Stop. Get out of here right now. I will call the police. Get out of here. Hey. Don't drink that. He put something in that. Don't drink that. No idea what you're talking about. Did you see that? I saw it. There's nothing in her drink. Didn't -- I see wine. Then you drink it. She's going sit with us now. Whatever. We're getting out of here. Thank you. Thanks a lot, girls. You're welcome. Have a good day. Reporter: Time to meet these brave college students. Hi, I'm John Quinones with "What would you do?" I've seen the show. Reporter: You doesn't give them much time at all. They were just creepy and in her face when they were fiddling with something, I'm like, this looks really suspicious. Reporter: Even before that, you asked her, join us, I took that class. Did you take that class? I didn't take that class. Reporter: You didn't? No. Reporter: We roll again. This woman watches as the pill goes in. And her friend sees the straw stirring something. And now Lauryn is back. Hey! Hey! . Reporter: They say anything? There you go. Reporter: A few minutes go by and we tell our actress to act like she's feeling the and facts of the drug. I don't feel so great all of a sudden. It's hot in here but we can just walk outside and put some ac on in the car. We'll take you home. Reporter: She seems troubled. We'll give you a ride. Here, here, let him take the bag. Don't worry about that. Reporter: If the boys are gone, will they do something? One goes to get the car, the other says, I'm going to the men's room for a second. What happened? They slipped her something. Reporter: Wait, they're telling Tracy. They might have slipped her a Mickey or something. They wanted to take her home. Reporter: He offers some help. You all right, baby? I don't feel good. You want a ride? They have all my stuff. Reporter: But he won't push it. Hey, darling. He's got the car outside. Reporter: Now the guys are back to get their prey. I got your bag. Ready? I can just go out there. Go get the car, dude. I got it. Reporter: They sit and watch as she staggers out the door. Time to tell them it's "What would you do?" Thank god. I thought she was going to be raped or something. Reporter: Why not stop them? We tried to. We told the waitress. Reporter: But as far as you getting personally involved? I would. He would have taken them out. Reporter: What stopped you? I didn't see him put anything in there. Reporter: And then, a surprising revelation. It happened to me before. When I was in college. Somebody put something in my drink. They took me out to the car. Reporter: Why not stop them before they took her out? Well, because I'm five foot tall. How am I going to stop them? Reporter: And now day turns into night. Just going to go the bathroom really quick. Yeah, sure, yeah, yeah. Reporter: This next patron sees the pill drop in. He tries to play it cool. They just roofied her drink. Are you leaving right now? No, I'm going out more a smoke. Making it look like I'm doing something, not just ratting them out. I'll be right outside. Reporter: While he's out, we tell the guys to drug the drink again since this woman missed it the first time. What are you doing? Guys -- I didn't see that, did I? See what? You put something in that girl's drink. I just -- I saw you! I can't watch this. You're so bad! Reporter: She's stunned. Will she blow the whistle? Hey. Hey, there you are. Reporter: Now Lauryn's back. Yeah, that's it. Reporter: And all she can do is just watch. That's when this man makes his move. These two guys put something in your drink -- I don't. I was watching your college drama. It was pretty entertaining. Reporter: Now that he's got the ball rolling, will she step up too? Did you guys see anything? I didn't. I don't know what they're talking about. Just mind your own business, sir. My nephew's a state trooper, so, that's why I'm not letting these guy goes anywhere. You want me to call 911? 911, what's your emergency? I'm at the mason jar and I just witnessed two gentlemen drug a woman's drink. Reporter: But he doesn't stop there. Anthony nigito heads over to the entrance, takes off his hoodie and then, to our surprise, ties up the exit. What's going on here? I'm John Quinones with "What would you do?" You got to be kidding me. Reporter: Show me what you did over here. I'm not going to let them leave. I tied it to the door and I'm going to cover it with -- Reporter: That is amazing. I always like to joke with everybody that my mother raised me right. Reporter: Consequences can be serious. For all of them. Can you stand by and do nothing. Reporter: You wish you would have done more? I was afraid of them, if they do that to me the cops come, what will they do to me? That was my fear. As a woman. Reporter: That's very legitimate. Yeah, but that's and I will toss and turn about this for a long time. Reporter: But fear doesn't hold back everyone. Hey, hey, hey. Reporter: Throughout the day, many people do come to Lauryn's rescue. Don't drink that. Back up. You want to test me? We got kids. You don't do it. Make your move. Now. Why? I'm going to get her stuff. You need to move. As a woman, I felt the need to protect another woman. And I was hoping that somebody would do that for me. In my life, I have been blessed to be around people who are
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