While appearing on the season premiere of Showtime's "Desus & Mero," the former "Late Show" host shared a story about the time he got into an argument with the "Once Upon a Time...in Hollywood" director after seeming to poke fun at his appearance.
"Is there any famous beefs you got into that you can talk on? Or do you have to sign like NDAs or?" co-host Desus Nice asked Letterman, who replied, "I got into a great fight with Quentin Tarantino. This was really good."
"There was one guest on the show and her girlfriend was someone [Tarantino] was dating. Famous star. So famous I can't recall the name," Letterman recalled. "And I was saying, 'No, you're not dating Quentin Tarantino.' And she said, 'Yes, yes I am.' And I said, 'No please tell me this isn't true.' Now I'm joking!"
"I'm thinking the idea is Quentin Tarantino is this movie store nerd from when you were able to go take out movies from the store. He was a self-described movie nerd," he continued. "Now I'm pretending that I'm stunned this glorious movie star is dating this little squirrelly guy."
According to Letterman, Tarantino called him two days later.
"He starts screaming at me, 'I'm gonna beat you to death, I'm gonna kill you, I'm coming to New York, and I'm gonna beat the crap out of you. How can you say that about me?'" Letterman said. "And I said, 'Quentin, hang on a second.'"
The comedian then got his producer to pick up the other line so they wouldn't think he was "making it up." Letterman said Tarantino went "on, and on and on -- like the guy is full-blown clinically goofy."
The "My Guest Needs No Introduction" host said he then asked Tarantino, "How do you want to do this? Bat or fists?" Letterman claimed the director chose a bat to "beat the hell out of" him.
"There's no cooling off," Letterman said. "It just keeps blowing up." As Letterman explained, the two men set a date for Tarantino to come to fight him but Tarantino was a no-show.
Years later, when Tarantino was promoting "Inglourious Basterds" on "The Late Show," the "Pulp Fiction" director apologized. And Letterman said he joked about the whole ordeal in their interview.
Watch Letterman recall the story in the clip above.