Robert will star as a dad-to-be who has to race across the country in time for his child's birth, with Zach playing what the mag called an "unlikely travel companion."
The film will find Zach reuniting with Todd, who directed him in this summer's surprise hit "The Hangover" – which, with over $240 million in box office grosses, has become the highest-earning R-rated comedy in history.
"Due Date" could potentially start filming this fall with a summer 2010 release in mind.
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