Some of the fighting in “Fight Club” was a little more real than some fans realize.

On Monday, Edward Norton was on “The Tonight Show Starring Jimmy Fallon”, and he shared a story about how he actually punched Brad Pitt during filming on the classic David Fincher film.

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“It’s the first punch in the movie and I hit him in the ear,” Norton recalled. “Fincher came up to me and said, ‘Hit him, connect with him somewhere.’ I didn’t know what to do and I hit him in the ear.”

He then remembered Pitt’s reaction in the moment.

“He says in the film, ‘Ow! Why the ear?’ Yeah, that was real!” Norton said.

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Norton also talked about the new film he directed, “Motherless Brooklyn”, including cast member Alec Baldwin.

In praising Baldwin, Norton actually offered up his own impression of the actor and his method acting style.