Kids arrived at comedian Stephen Colbert's studio home, dressed as characters played by guest Tom Hanks - but it was Damon's soldier outfit that earned the most laughs.
After kids dressed as Toy Story's Woody, an astronaut from Apollo 13, Castaway's bearded Chuck Noland and the various characters from Hanks' new movie Cloud Atlas showed up as trick or treaters, it was Saving Private Ryan star Damon's turn to burst through the door, raging, "What is the deal, Hanks...? You asked me to come down here. You said it was for charity... I've got better things to do. I could be drunk right now in a movie theatre heckling Argo."
Argo is the new movie from Damon's best pal Ben Affleck.