THE HANGOVER PT I: i keep forgetting about the gawddamn tiger

Three buddies wake up from a bachelor party in Las Vegas, with no memory of the previous night because one of them was stupid enough to drug them, including himself. with the bachelor missing because his character is a no-nonsense type that wouldn't mesh with his inept groomsmen, the others make their way around the city in order to find their friend before his wedding, which they conveniently do.