In Knocked Up, a one-night stand and an unplanned pregnancy are the fodder for an astoundingly, catastrophically tragic comedy. What's so funny?

An innocent child is forced into an experiment to see if a pot-bellied, pot-smoking, porn-peddler can get his shit together and become a responsible adult. The dad-to-be is an utter loser: he's crass, irresponsible in the extreme, sexist, and incapable of learning from his mistakes. Even his best efforts to impress are miserable failures...