In terms of the story, the time flipping narrative script is stronger than a punch from Mike Tyson, who makes a cameo that is way more bizarre than he is in the preview. There are some potholes in the script, but the comedic performances from the three leads are strong enough to keep you laughing right over them. And with the three leads doing great, the film also benefits from some great supporting characters including Ken Jeong, who seems to be everywhere these days.
It's tough to make a lights out comedy. Each laugh needs to be timed correctly, the story has to be kind of there and the stars need to be able to deliver. "The Hangover" is mind melting in it's hilarity, but I will say that is certainly delivers on warming the brain (and the heart?, no just kidding) a little bit. It's funny, raunchy, and unlike the situation facing the characters of the film, actually something that people will remember.