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Jessica Biel has signed on to join Scarlett Johansson in the upcoming horror flick Making of Psycho, according to Deadline.

Biel, who reportedly is now engaged to Justin Timberlake, will play Vera Miles ... the character who discovers Mrs. Bates' bones.

Johansson, 27, will star as Marion Crane which was the role famously played by Janet Leigh in the original 1960 thriller.

Other actors that have signed on to the Alfred Hitchcock film include Anthony Hopkins, Helen Mirren and James D'Arcy.