First pics of Scarlett Johansson as Janet Leigh

The first pictures of Scartlett Johansson playing Janet Leigh in the forthcoming Alfred Hitchcock biopic have been released online.

Director Sacha Gervasi, who's helming 'Hitchcock', said that the crew was amazed at the transformation of the 27-year-old actress into the star of 'Psycho'.

"When we took that still of Scarlett behind the wheel and put it up against the still of Janet behind the wheel in Psycho, it was eerie," he said.

"The extent to which Scarlett was able to channel Janet [was] a real surprise. She brought it in such a way that no one really anticipated."

Further pics have also been released, of Helen Mirren playing Hitchcock's wife Alma, Anthony Hopkins as Hitchcock himself, and James D'Arcy as Anthony Perkins.

The film tells the story of the making of 'Psycho', and also features Jessica Biel as Vera Miles, Ralph Macchio as screenwriter Joe Stefano, Toni Collette as Hitchcock's assistant Peggy Robertson and Danny Huston as writer Whitfield Cook.

It's released on November 23.