"The Hangover" star Ed Helms has signed on to play Clark Griswold's grown-up son in an update of comedy classic National Lampoon's Vacation.

Producers are still hoping to bring Chevy Chase and Beverly D'Angelo back for the revamp, but reports suggest they've settled on their Rusty, the character played on the big screen by former child stars Anthony Michael Hall, Johnny Galecki and Jason Lively.

In the new film, Clark and Ellen Griswold’s son heads off on his own family vacation only to realize he has inherited his father's clumsy, accident and trouble-prone ways.