Transcript for Twin Sisters Separated at Birth Reunite
See what's new at projectluna.com Test Text1 plain Samantha fuderman got a Facebook message from a stranger that would change everything. The woman sending the message pointed out both she and Samantha had been adopted and they looked very, very similar. Could they fw long lost sisters? Two young women are about to get news that could inexorably also alt altar their lives. They're going to find out if they were identical twins separated at birth. It's a life changing thing whether you're twins or not. Are you both ready? Okay. Samantha always knew she was adopted. I was born in Korea and four months later I arrived at JFK airport where apparently all babies don't come from. And yeah, I met my family for the first time. She grew up in New Jersey and later moved to Los Angeles to be an actor, and a working one at that. Landing roles in films such as "Memoirs of a geisha and "21 and over." Do you know this guy? Why? Because I'm asian? Oh, wait, I do know this guy. And like so many other 26 years old, Sam has a profound online footprint and to that point often performs in comedy videos she and her friends posted on youtube. A year ago, she received a very random message on Facebook. The Facebook request was weird. I thought it was a creepy fan of my friend or something. Reporter: The request was sent by a stranger living 5,000 miles away. I am French and live in London. About two months ago my friend was watching one of your videos and he saw you and thought we looked really similar. Like very really similar. Reporter: That face looked for all the world like a reflection in her own mirror. And that began a journey for two women that now sought to uncover the answer to the only question that really mattered. Were they twins? I don't want to be too Lindsay lohan, but I was wondering where were you born? The possibility of however remote of playing a role in a real life parent trap proved understandably irresistible. We're like sisters. Sisters. We're, like, twins. Anais was adopted as an infant by a family in France. Oh, hey, this is my brother Matt. Reporter: Her digital detective work intensified and she tracked down of Samantha's youtube videos about being adopted. You're being ridiculous. You know what? You were adopted. What? I'm just kidding. I've always known that. A touch of hesitation, overwhelmed by massive mu kul cu -- mutual curiosity, they set up a time to chat. I am about to go on line to Facebook and then Skype and Skype my potential twin sister, which is really crazy. Reporter: The power of social networking rendering a vast world in an instant, a very strange and intimate place. My connection is really bad. Oh, my god, you're european! This is a really weird experience. This is so weird. I don't want to get my hopes up, but I think somewhere in the pit of my gut, I knew that it was probably true. Anais. From there, a deepening friendship, talking almost daily and culminating in London with their first in-person meeting. First things that you said? I poked her head. To make sure she was real? Was there a sense of relief that finally you could get that moment out of the way? And then just set about being together? Yes and no. I think I wanted to live in that moment for a long time. Reporter: That shared moment sparking so many more. There are visits to Los Angeles, travels back to South Korea, and a reunion here in New York. Each time believing just a bit more. So how are you alike? Same laugh. Same shortness. Hey! Sorry. Reporter: I am going to ask you a question. I want you to answer at the same time. Coke or Pepsi. Coke. Reporter: One pet peeve? Shower curtain touches me. I hate that. Oh, my god, that's the same. I hate that. Reporter: Despite the small similarities and the inarguable physical resemblance, Sam and Anais turn to DNA testing and finally the answer is there. An answer they share with Samantha's adoptive mother. I'm going out on a limb here. You're sisters, aren't you? Yeah. Holy . Did it make you feel good to know that you're identical twins? Yes. I think it was a relief in a way. Even though we knew. But if there's a slight 1% chance we might not be. Reporter: They decided to make a documentary. They're calling it twinsteres. Hoping their experience inspires other adoptees on their own journeys. Your necklace, what does it say? And the significance of them to you is what? It says best friends forever. And I got them for Christmas because I never had them growing uh. It sounds really cheesy, but I think we need those little kids moments. And those cheesy moments together. The feeling on Christmas, when you open up the present and it's the one you were asking for. That pure feeling of joy. Reporter: Well, now that you are together, has it changed the idea of the future for you now? I think I feel a lot more confident knowing. It's like yeah, I found my second half back. Reporter: Reali -- Realizing I have an I dent call twin sister, it dropped a bomb on me. Everything and anything is possible in the world. Now literally any doors open. Reporter: I'm josh Elliott in New York.
This transcript has been automatically generated and may not be 100% accurate.