Transcript for Manti Te'o Hoax: Was He Duped or Did He Know?
It just one of four hours this bizarre story has sparked astonishment confusion and transformed a beloved college football star -- the internet's. Newest punch line man tied tale inspired countless fans when he led. Notre Dame to -- epic winning season after the tragic death of his longtime girlfriend that is. Until they learned she was a figment of someone's imagination but who. Good Morning America -- -- Josh Elliott has the latest. It seemed like a tragic love story -- -- most beautiful girl. I've ever met. Not because of her physical group -- of the period of her. Her character. And -- is this is -- tied -- in October talking about the girlfriend whom he believed had just died and I'll sentence. Signed. That sounds really. -- -- you until Wednesday tale notre Dame's all American linebacker and Heisman finalist. Was the focus of the most inspiring college football story of the year. Now questions arise is the star athlete the victim of a mysterious and elaborate hoax as he says. Or was he a part of it all along. -- was known for his big hits on the field. And his big -- often. His story of overcoming the loss of his grandmother. And that his girlfriend -- Nate cuckoo within hours of each other last fall even for going to -- funerals to play a big game. Only added to his growing legend. She named conversation that they -- finally have some he -- -- is still there and -- you play. And you know you army through the way you put. His performance would turn him into a mega star. While the raw emotion displayed humanize to. I knew it. Well now tale when Notre Dame say. -- his love and tears were real his girlfriend was not this was a very elaborate. Very sophisticated hoax. Perpetrated. For reasons we can't fully understand. In a statement Taylor said quote to realize that I was the victim of what was apparently someone sick joke and constant lies. Was and is painful and humiliating end quote. Not only was his girlfriend -- coo -- would not real. But according to dead spin the sports website which broke the story the pictures purported to be could -- -- are actually of another woman. Very much alive. Who says she doesn't even know -- somebody this morning on GMA I spoke with Timothy -- one of the writers and the dead spin piece. A lot of people are -- -- suspicious when -- says that he had no idea and he was just the soccer and that's because. You know why why would somebody go to such great lengths. To tiptoe -- have markets. Was tale really the victim of the Internet hoax called -- fishing we know that this is a phenomenon that -- cat fishing day. People do it you know because they like. Playing practical jokes this one if that's what -- obviously went weak too far and it is really. Rule. Need showman knows all about -- fishing for recording the terms an Internet fraud who pretends to be someone they're not going. The character they created although they knew it was false. Was not only an extension of themselves but also somebody that they truly believe. Has a positive effect on the people with whom it interacts. There from please -- -- -- crowded chatting with a he felt for make it turns out my crush. It wasn't my -- Only to discover she was really a middle aged mom named Angela Schulman light and that -- Played out in the documentary catfish. Now also -- hit series on MTV. I'm hitting the road. To help people meet -- -- -- loves for the first time our imagination plays a huge part in creating an image if someone. It gets cagey about about meeting up and is reluctant or is constantly. Creating excuses as to why they can't meet up at the last second. That's clearly a red flag. Questions about -- story are being raised was he somehow involved in the hoax. Notre Dame officials say their relationship was exclusively. Online. So why -- -- -- father reportedly tell one paper that his son had met could -- after a game at -- years ago. And that they'd spent time together in Hawaii. Two people reached out to me. Over a month ago asking for my help in. Uncovering the truth behind this profile and from what they tell me. I get the impression this story goes a lot deeper than just. The relationship between -- and -- And why even after -- -- -- school officials of the -- back in December did no one go public to set the record straight. Now -- it appears that the stories. Were wrong. Fabrics mediated. That he was -- where he perpetrated a hoax people know exactly what happened. On the campus of Notre Dame today nothing but stunned dismay. Of course Farris found suspicious parts of the story. Play it it's extremely hard to believe -- Somewhere and could do something so hurtful and -- And across social media and the Twitter verse the mystery spawned a new -- him. Tailing. People posting pictures embracing imaginary friends. And for sale seen here today still no answers to an ever growing list of questions. For Nightline I'm Josh Elliott in New York.
This transcript has been automatically generated and may not be 100% accurate.