Venice Film Festival 2012: Michael Shannon chills in "The Iceman"

(CBS/AP) VENICE, Italy - "The Iceman," a film about real-life hitman Richard Kulinski, is making its debut at the Venice Film Festival on Thursday.

Michael Shannon plays the killer-for-hire, who conceals the truth of his occupation from his picture-perfect suburban family.

Pictures: Venice Film Festival 2012

Israeli director Ariel Vromen says he fought for years to get Shannon into the role, fending off "more obvious choices."

Vromen said he wanted Shannon, who earned an Oscar nomination for his role in "Revolutionary Road," because "he comes with a darkness," explaining it was more effective to "make that darkness more refined" than to "bring someone who is very cheesy" and try to add it.

In the film, Shannon stars alongside Winona Ryder as his unsuspecting wife and Ray Liotta as the Mafia boss who recognizes hit-man potential.

"The Iceman" is being screened out of competition at the Venice Film Festival, which runs through Sept. 8.