Credit: Steve Granitz/; Anita Bugge/

Jessica Biel is the consummate professional.

The actress, 30, has just signed on to the cast of Alfred Hitchcock and the Making of Psycho, Deadline reports. Her colleagues in the moviemaking biopic include Anthony Hopkins as the legendary director, Helen Mirren as his wife -- and Scarlett Johansson as Janet Leigh, who played Marion Crane, the infamous shower murder victim in the horror classic.

Biel is set to play actress Vera Miles, whose character, Lila Crane, Marion's sister, discovers the skeletal remains of Mrs. Bates. Actor James D'Arcy will reportedly play Anthony Perkins (a.k.a. Norman Bates).

As first reported by Us Weekly, Biel is now engaged to love of five years Justin Timberlake -- who happens to count Johansson, 27, among his many conquests. "They've hooked up several times over the years," a pal told Us.

Just last September, Timberlake was spotted visiting the We Bought a Zoo actress' NYC apartment after a raucous night of "hardcore flirting" at downtown hotspot 1Oak.

These days, Johansson is dating ad exec Nate Naylor.

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