Actress Scarlett Johansson was terrified shooting the iconic Psycho shower scene with Anthony Hopkins in her upcoming movie Hitchcock - because she couldn't get his portrayal of serial killer Hannibal Lecter out of her head.

The Avengers star portrays Psycho star Janet Leigh in the film, which examines the story behind the 1959 classic Alfred Hitchcock horror movie, and she she admits the thought of fighting off the Silence of the Lambs villain in a bathroom was one that kept her up at night.

She tells V magazine, "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.

"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."

But otherwise, Johansson thoroughly enjoyed playing the scream queen - and had no problems stripping off for the shower scene.

She adds, "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. 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."