Justin Theroux will direct 'Swear to God'.
The 'Wanderlust' actor will make his feature film directorial debut on the comedy starring Will Ferrell and Steve Carell and he is set to rework the script before he takes the reins on the Warner Bros. project, according to Deadline.
The original script was written by 'Due Date' scribes Alan Cohen and Alan Freedland.
Will is to play a narcissistic hedge fund manager who thinks he has seen God in the movie, which he is set to begin filming after working on 'Anchorman 2'.
Justin could also direct 'Zoolander 2' after he wrote the script for the comedy sequel.
While it has been delayed, Ben Stiller has promised the movie will be ''bigger and better'' than the original.
The 46-year-old actor - who plays clueless model Derek Zoolander - previously revealed the sequel will be set in Europe 10 years after the original and will see his character and Owen Wilson's alter-ego Hansel no longer relevant on the fashion scene.
He said: ''I don't want to give away too much, but it's basically Derek and Hansel 10 years later - though the last movie ended on a happy note a lot of things have happened in the meantime. Their lives have changed and they're not really relevant anymore. It's a new world for them.''