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Scarlett Johansson recreates Janet Leigh's infamous shower scene from Psycho in the upcoming movie Hitchcock, and the 27-year-old beauty says that although she didn't care about taking it all off on the set, facing Anthony Hopkins wielding a 12-inch kitchen knife was an altogether different story.

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"You have got to be brave, get into the shower, and face Anthony Hopkins as Hitchcock jabbing you in the face with a 12-inch kitchen knife," she tells V magazine. "As much as Anthony Hopkins is a pussycat, he's terrifying. Maybe I watched Silence of the Lambs too many times when I was a kid. Maybe I was having some flashbacks. So I didn't need too much preparation for the scene."

In select theaters November 23, Hitchcock recounts the struggles of making the title filmmaker's seminal 1960 horror film.

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"We only had the luxury to shoot the scene for a day, and everybody was feeling very nervous because it involved water and nobody wants the actor to get wet," continues Scarlett. "They were concerned with modesty and all these things – but I don't care about any of that stuff and Janet Leigh never did either."