Reporter: The following preview is rated "Q" for "What would you do?" He put a ring on it! Reporter: In a world where love conquers all -- You found your soul mate. He is so wonderful. I found it. I... See More
Reporter: The following preview is rated "Q" for "What would you do?" He put a ring on it! Reporter: In a world where love conquers all -- You found your soul mate. He is so wonderful. I found it. I found it! Reporter: -- Three friends -- Oh! Reporter: -- And one perfect dress -- This is the one. You look like a princess. Reporter: It's a time for celebration. Let's toast. To love. Reporter: Until -- shrieks of joy become screams of horror. "What would you do?" Presents "The malbec massacre." Oops. Reporter: It's a "What would you do?" Horror story, and it begins at I do, I do bridal salon in morristown, New Jersey. Our cameras are veiled and rolling as our seamstress Traci brings out Lauryn's dress. Thank you so much. I'm so excited for you to see it. Do you have your shoes? No. Reporter: Our bride-to-be forgot her shoes. Can you guys just hang onto this? Yeah, yeah, yeah. Reporter: While they wait for her to return, our bridesmaids prepare a toast. Cheers. Reporter: Suddenly, this $3,000 wedding dress is a bloody mess. Oh, god! Reporter: These real customers are stunned. And this woman even gets up to help. Just put it back in the bag. Kaira, really? I know. I didn't mean to -- it just fell out my hand. Please don't say anything when she comes back in. Reporter: Will she keep quiet while our bridesmaids play dumb? Wait, you guys, no. Oh, my god. The store must have done it. When I worked on it earlier today, there was nothing wrong with it. What did you guys do to it? We haven't even seen it. You didn't take it out of the bag when I went to the car? No. No. I'm sorry, did anybody see what happened to this dress? Did you see what happened? No, I was just sitting here. Well, this was obviously negligence on their part. So I think we should just go and we'll -- You still have two more payments on this. You obviously did something. No, I didn't. You had to have. Reporter: Our seamstress is left holding the bag. She has two more payments. When I brought it out, it didn't look like this. Now I'm going to be stuck with the whole thing. Are you okay? I don't know what happened. I was sitting here and I just looked and there was wine all over the floor. I feel bad for you but I don't want to say I saw it happened but I didn't. Thank you so much. Reporter: We send Lauryn back looking for a refund. I'm not paying for the rest of this. This is on you. Reporter: And now, the woman who didn't say much to our seamstress gets up to make a little confession to our bride. Can I talk to you for a second? Yeah. It was your friend. The one with the blonde hair. What did you see? The blonde haired girl did it? She's my maid of honor. I didn't even know they had wine. I'm really sorry to tell you that, but I don't want to see her pay for that dress. Reporter: Even the woman's daughter joins in. -Omg, omg. I didn't mean to do it, I didn't mean to do it. The friend should admit that she did it. Yeah. What kind of friend is she if she's going to hide something like that? Reporter: Time for us to let them know those friends were faking it. Hi ladies, I'm John Quinones. Oh, wow, I saw you on TV. Reporter: They were actors. Aw, man. Reporter: Did you actually see it happen? Yes. Reporter: And you stayed quiet for a while. I feel terrible for the bride but I didn't want to see her pay for the dress. I said we're like the rats, we ratted them out. Reporter: And the woman reluctant to rat? She felt the evidence was just too circumstantial. I didn't see it drop. I just saw the gown, the wine was on the floor and the girls were like -- you know, so I was just trying to help. Reporter: You weren't gonna point the finger at them? No, I was not. Always the bridesmaid, never the bride. Aw. Reporter: We paint the salon red -- -- many more times over the course of the day. And our bridesmaids get their share of dirty looks. They'll just order her a new one. It will be okay. I didn't like it that much, anyway. Reporter: And from these ladies who brought their own wine, some cleaning tips. What do I do, guys? Oxy clean. Reporter: There's advice on the moral thing to do. If I were you, I'd just tell her. Reporter: And from this woman, well -- we'll let her do the talking. Did it come like this? I don't know. I didn't open the dress until you came in here, so I don't know. The girls spilled the wine on the dress. It was an accident, but that's the truth. You guys aren't telling me? What the heck? We didn't have any wine. We haven't even seen the dress. Oh, my god, her tongue is going to fall off for lying. Tell her. Reporter: They've got some sound advice. Don't drink red wine. That's like rule number one of getting married. You don't have red wine by a wedding dress. Reporter: Champagne, okay. Totally fine. Reporter: We'll break that rule one last time, and to make an even bigger splash, we invite a real bride-to-be to join in on the fun. So you wanna play along with us? Yeah, I'll do it. It sounds like a fun prank. Reporter: Meet Kim Milan. Her mother and sister don't know this is "What would you do?" What will they do when our careless culprits mess with the very dress Kim is trying on? I don't know, I really don't know what my mom's gonna do. Reporter: Time to find out. Kim, join our toast. Cers. Oh! Reporter: We're sensing a bit of distress. Do you know how much that costs? I have no idea. That's $3,000. I don't think it's gonna come out. You're her mom? Can I go ahead and get a credit card from you? Reporter: With that, Kim's sister flees the scene of the crime. Unfortunately, you're going to have to pay for the dress, unless these girls want to pay. No, I can't even afford this one. So is that going to be American Express or Mastercard? Wait just a second. I think you don't realize what happened. Reporter: Mom reviews the facts like a defense attorney. There was red wine here that we didn't bring. Okay. She was offered a glass of red wine. They toasted her too hard and it fell on the dress. We didn't bring the wine. But she's in the dress. I understand that. I think we need to talk about it more before you ask me for my credit card. Reporter: She's right, her daughter is innocent and our bridesmaids are guilty as charged. Time for us to come clean. Do you have a credit card for me? Are you kidding me? Did she know? Reporter: Of course. She was in on it. She is so dead. Reporter: You just ran, you just got out of here. It was like secondhand embarrassment, so I just had to
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