Christopher Walken joins 'Jersey Boys' film cast

"Jersey Boys," the Tony-Award winning Broadway musical, has already grossed more than $1 billion in New York City and around the world, so it was only a matter of time before it hit the silver screen.

Deadline reported Tuesday that the incomparable Christopher Walken has been cast in Clint Eastwood's "Jersey Boys" adaptation, as mobster "Gyp DeCarlo, who helps four young singers build their careers and pay for their debts.

Eastwood may have cast Walken for the mob boss role, but the film's four young stars will be culled from the ranks of lesser-known stage actors. Variety reported last week that the film had cast John Lloyd Young, who already played Frankie Valli in the original show, Erich Bergen, Michael Lomenda and “Boardwalk Empire” star Vincent Piazza as "Jersey Boys'" Four Seasons.

Deadline said that Eastwood could add other big-name stars to cast.