Robert Downey Jr. is to join the red hot star of The Hangover, Zack Galifianakis, in the Todd Phillips directed comedy, Due Date. Downey Jr. will play a dude rushing home to see the birth of his first child, with Galifianakis travelling with him. The film is described as a road trip comedy, as the mismatched pair spend a lot of time bickering and whatnot; Phillips himself describes it as a "buddy comedy without the buddies," and frankly, after directing comedy gold like Old School and The Hangover, he could describe it as "The Golden Girls with middle-aged men" and I'd be on board. You'll next see Galifianakis in G-Force, which is released in Irish cinemas this Friday, while Downey Jr. has Sherlock Holmes due out at Christmas.