For over 20 years, woody Allen has lived under a cloud of suspicion, and tonight, he's hoping to clear the air. Responding angrily and defiantly to allegations that he molested Dylan farrow, the... See More
For over 20 years, woody Allen has lived under a cloud of suspicion, and tonight, he's hoping to clear the air. Responding angrily and defiantly to allegations that he molested Dylan farrow, the daughter of his expartner Mia farrow in 1992. Last week, the now 28-year-old Dylan recounted in "The New York times" kmark what she said were the details of the horrifying assau assault. Tonight, Allen insists that's a vengeful, fabricated smear. Here's ABC's juju Chang. Of course, I did not molest Dylan. Tonight, that flat-out denial from the world renowned director, answering charges for the first time in 20 years. I loved her and hope one day she will grasp how she's been cheated out of having a loving father and he squarely placed the blame on Mia farrow. One must ask, did Dylan even write the letter? Or was it at least guided by her mother. The reexclusive director speaking out to Dylan farrow's open letter in a blog in "The New York times" website. Dylan broke her silence after woody Allen was honored at this year's golden globes, accepted in his absence by his long-time friend and leading lady, Diane Keaton. He's made 74 movies in 48 years. In her letter, Dylan describes in detail what she says she remembers happened to her. What's your favorite woody Allen movie? Before you know, you should know that when I was 7 years old, he led me into a dim closet-like attic on my second house. He told me to lay on my stomach and play with my brother's electric train set. Then he molested me. It's an allegation that Allen has always denied. His reaction to Dylan's letter is overwhelming sadness. It revives the fight that he had with Mia farrow 20 years ago. It all began when woody Allen fell in love with another of his leading ladies, Mia farrow. Over the course of 12 years, they had three children together, two adoptive, one biological, in addition to mi a's other adopted children. Farrow auz was Allen's artistic muse in many films. That collaboration came crashing down during the filming of "Husbands and wives." I thought it was a good idea to have a baby. I don't think it's such a good idea. Why? That's when Mia discovered six naked polaroids of her then 19-year-old adoptive daughter on woody Allen's fireplace mantle. The scandal became a prolonged tabloid obsession. In the midst of the storm, Mia went back on the set of "Husbands and wives" to film their final scene. You were so beautiful in that black dress. Really. Don't do that. Sun Yi moved into woody Allen's house and within a few years, they were married. The breakup hit the entire family hard. "Vanity fair" writer spoke extensively with the family last fall. The revelations were absolutely devastating to this family, according to the eight children I spoke to. Because here he was, the defacto dad in the family for a long, long time. And so the fact that suddenly, their sister was sort betrayed the mother and ran off with woody and he didn't act like anything had gone wrong. Perhaps no one was more affected than 7-year-old Dylan. A few months after the split on August 4, 1992, Dylan says Allen took her to that attic room in farrow's country house. And did she tell you explicitly that she was molested in the attic? She told me that she remembers very clearly what happened to her in the attic and what she was wearing when she got there and what wasn't on when she left. So then she told me, my advice to the 7-year-old Dylan today would be, be brave, testify. So she told you explicitly that she had been molested. Not just that she was made to feel uncomfortable. She told me that she was made to feel very uncomfortable. Mia farrow videotaped Dylan's account of what happened and told the family's pediatrician, who by law had to alert the authorities. Connecticut police launched a criminal investigation, which included an independent review by the Yale New Haven sex abuse clinic. After a six-month exhaustive investigation, that group concluded not only that the molestation did not occur, period, but they concluded that it was caused by either Mia farrow coaching Dylan inappropriately, or Dylan's inability to distinguish between fantasy and reality. Criminal charges were never filed against woody Allen, but the state's attorney who was in charge of the investigation at the time issued a statement saying he felt there was probable cause to charge the legendary director, but he chose not to in order to spare Dylan. I spoke to the prosecutor today and his sense was that, while he kept saying that, I stand by the remarks that I made that many years ago, but that with the probable cause, he -- it wasn't that he felt that no criminalalty occurred, but that he didn't think Dylan could make it through a trial and that for her sake he wouldn't press forward with a trial. I know that's what he said, and I think we brought him to task at the time for making an inappropriate statement like that. He either brings a case or he doesn't bring a case. But Allen lost the custody battle and an appeal. He was only allowed supervised visits with the children he had with farrow. And the custody judge called Allen a willfully inappropriate parent. He even cast doubt on some of the conclusions of the Yale new Haven center report, saying that the judge wasn't sure that the evidence conclusively proved no sexual abuse occurred. All of thf left a residue of doubt over what kmaktly happened that day. A doubt that was brought to the surface again this awards season. Thank you. Reporter: Many observers are saying that Dylan has nothing to gain about all this. Why would she lie? I don't think she's lying. I think that Dylan honestly believes this happened. I think that it is a function of the fact that she was used in a pawn in the fight between Mia and woody. One doesn't become a pedophile overnight. You either are a pedophile or you're not a pedophile. Since Dylan's open letter in "The New York times," the battle between Mia farrow and woody Allen is being refought on TV. You don't have any comment on Dylan's letter? This photo from the day Dylan's letter went vital, he and his two adoptive daughters with sunyi, swarmed by the press. Is he a good father? I got to see a little bit of dynamic with his kids. Dr. Robert Whitey who made a four-hour sere on the famously reclusive filmmaker and recently spoked with a surprising Allen defender, his oldest adoptive son with Mia. Last week in "People" magazine, Moses came to his father's defense. Of course woody did not molest my sister. She never hid from him until our mother created the atmosphere of fear and hate towards him. I spoke with him personally when I was writing my piece for "The daily beast." He uses brainwashed without hesitation. Recently he reached out to woody, apologized and said let's get to. Woody was so happy to have one of his sons back. And woody and sunyi are enjoying a wonderful relationship with Moses right now. Dylan herself responded saying my memories are the truth and they are mine and I will live with that for the rest of my life. My brother is dead to me. As for the allegations that Mia manipulated her, Dylan strongly objects. My mother never coached me. She was distraught when I told her. She was hoping against hope that I made it up. And late tonight, an impassioned response from Dylan farrow to ABC news. For 20 years I have never waivered in describing what he did to me. Woody Allen has an arsenal of lawyers and publicists. But the one thing he does not have on his side is the truth. With the oscars just weeks away, some Hollywood insiders suggest this may cast a Schad dough of Allen's most recent movie. Do you think this might have an impact on how his career is perceived? I certainly hope not. I hope that people who participate in the voting for the oscars do so on the basis of the art itself and not the personal kwukt of in conduct of anybody.
This transcript has been automatically generated and may not be 100% accurate.