Mel Gibson is facing a big problem, as famed screenwriter Joe Eszterhas said he has irrefutable proof he's telling the truth about Gibson.
Eszterhas told the Today show, "I have a tape that my 15-year-old son made in the middle of a violent harangue."
Eszterhas claimed his son secretly recorded Gibson's rant on his iPad and he's considering releasing the video after Gibson called Eszterhas' claims "utter fabrications."
Eszterhas said, "I don't like to be called a liar."
In a letter to Gibson, Eszterhas accused the actor of making vile anti-Semitic slurs, and threatening the life of former girlfriend Oksana Grigorieva. He said Gibson also shared a violent sexual fantasy with his son during a trip to Gibson's remote mountain hideaway in Costa Rica.
"Mel shared with him a pornographic scenario that I could only call sexual butchery that he fantasized in terms of Oksana. My son Nick wound up snatching a butcher knife from the kitchen and sleeping with it under his pillow because he was so frightened," said Eszterhas.
The nine-page letter was obtained by Thewrap.com.
Sharon Waxman of Thewrap.com told INSIDE EDITION, "I think that his son took the recording, from what he says, in a moment of legitimate fear and panic because at this dinner in Costa Rica, apparently Mel Gibson was completely unhinged to people while they were cowering in the dining room."
The latest Gibson crisis is the talk of Hollywood.
INSIDE EDITION spoke with actor Michael Richards, who played Kramer on Seinfeld. You'll recall that Richards was taped having his own notorious meltdown at a comedy club in 2006.
"I am a fan because I respect his talent, this enormously gifted man. Let's see what comes out of it," said Richards.
Gibson and Eszterhas had a falling out over a script that he wrote called The Maccabees. Gibson called the script "substandard."