You shouldn't bring alcohol to your school prom.
Simon is graduating soon, and he and his friends are going to the prom.
Simon wants to do something special.
Simon buys a small personal gift for each of his friends.
Simon sneaks a flask of vodka in, for he and his friends to share.
His friends love the gifts and Simon feels satisfied with himself.
Before he even has the chance to share the flask, he gets caught and removed from the prom.