Michael Keaton Says Jack Nicholson Questioned His Workout Routine for Batman: 'What Are You Doing That For?'

Michael Keaton is reminiscing on his time filming Batman — and he's revealing who thought his workout routine wasn’t the best idea.

In a recent interview with GQ, Keaton, 72, looked back on his most memorable roles, including Batman in Tim Burton’s 1989 film. The actor said it was a “ballsy” move for Burton to cast him in that role given he had mostly taken on comedic jobs up until that point.

“When they said ‘We’re thinking of doing Batman,’ I said, ‘Wait, you’re thinking of making a movie about Batman?’” Keaton said. “The fact that Tim said ‘That guy, I want that guy’ … The fact that people cared one way or another so much is still baffling."

He continued, “But that was a ballsy move on his part. We also had a nice working relationship from ‘Beetlejuice,’ so he felt that he and I could get along and would work well together.”

Thinking back to his time on set, The Flash star said he had an encounter with Jack Nicholson, who played the Joker in the film, that stuck with him. Keaton remembered “training to be really fit” for the role when Nicholson passed by and asked why Keaton was working out.

“He said, ‘What are you doing that for?’” Keaton recalled. “I didn’t have an answer for him and he just walked off. I approached it totally wrong. It’s better to be really small and little and thin inside the thing. You can move, you can breathe inside.”

Keaton joked that he was not used to playing a character in an action movie, so he didn’t know what he was supposed to do.

“I don’t know what I was thinking, I just thought, ‘I’m an actor, I’m gonna do all this stuff!’” he admitted.

The year prior to his superhero debut, Keaton and Burton worked together when Keaton took on the leading role in the 1988 movie Beetlejuice. After Batman, Keaton also returned to the franchise for the sequel, Batman Returns.

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Later this year, Beetlejuice Beetlejuice, a sequel to the first movie 35 years ago, will reunite the pair. Keaton is reprising his role, and he said in June 2023 that the remake was fun to do.

"F---in’ great," he said. "It’s the most fun I’ve had working on a movie in I can’t tell you how long."

He also gave insight into what fans can expect: "We’re doing it exactly like we did the first movie," he said at the time, adding that he and Burton stuck to their agreement from "years and years ago" that a sequel "has to be done as close to the way we made it the first time. Making stuff up, making stuff happen, improvising and riffing."