Teenagers often fantasize about begin big and important, although in reality they have no clue what that means. That is the same case with Seth (Jonah Hill) and Evan (Michael Cera). They are best friends from high school. With the help of their nerdy friend Fogell (Christopher Mintz-Plasse), they manage to get into one of the wild parties with lots of girls and even more booze. There, they meet two hot girls Jules (Emma Stone) and Becca (Martha MacIsaac), and each of them tries to get into some action, but they keep failing big time. The goal is to go to college already experienced and with lots of knowledge. But, that doesn't seem to be happening for them. As the story goes on, we see them falling from one into another hilarious situation and trying to get out of each of them, but only manage to make things worse every damn time. And somewhere along the way, the audience gets to meet two very slow and dumb cops that come into the whole game, who not only don't arrest Fogell when he tries to buy alcohol with a fake id, but make friends with him and support him in everything he does. Are they dreaming or they have backup from the police officers?