You know Samuel L. Jackson as the charismatic star of movies like Pulp Fiction and the Star Wars prequels. But did you know that in his youth Samuel L. Jackson stuttered? It’s true. To overcome the speech disorder, Jackson eventually taught himself “to pretend to be other people who didn’t stutter,” and to use the word motherf—er to help him get through moments when he felt like he had to stutter. So that’s why he says it so much. That’s just one of the facts featured in the latest installment of You Think You Know Movies.

As a young actor, Jackson struggled for years with drug problems, finally entering rehab in the early 1990s. After getting sober, Spike Lee cast Jackson as Gator, a crack addict, in his 1991 film Jungle Fever. Jackson later called the experience “cathartic,” and a big help in his journey to quit drugs. The purple lightsaber Jackson’s Star Wars character, Mace Windu, wields was designed at Jackson’s personal request. It was also inscribed with three letters on the hilt, “BMF,” a reference to his famous Pulp Fiction character’s wallet, which read “BAD MOTHER F—ER.”

You Think You Know Movies? is a ScreenCrush original series that dives deep into the cinematic worlds of your favorite movies and freeze frames a few tidbits you might not have known. We’ve already tackled Star WarsThe Avengers and Spider-Man, but this time we’re celebrating the star of Pulp FictionDeep Blue SeaKingsman and many more. Watch more installments of ‘You Think You Know Movies?’ below and let us know in the comments what movies we should cover next!

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