It is the night before New Year's Eve. The parents are not home… Ben Pearson, a sophomore who got himself involved in a lie constructed by his friend Mike to act like they’re senior as a way to prank them for bullying one of their friends, Ben goes in way too deep by claiming he is a pro drummer to his senior crush Christine even though he hasn’t drummed a beat in his life.

When Ben and his friends were invited to attend a senior party for New Year's Eve, he agreed to perform his drumming talent on the night of, so he plans to get as drunk as he can as an excuse to play sloppily, but he’s never drunk alcohol before. While his parents were away, Ben took advantage of the empty house to host a get-together with his friends as a way to experience drinking alcohol for the first time before the night of the New Year's Eve party. Still, two seniors unexpectedly join the get-together, which puts Ben and his friends at greater risk of their ages being revealed before the big night.