Derek Thompson (Dwayne Johnson) is a tough, gritty minor league hockey player whose brutal style of play has earned him the nickname of "The Tooth Fairy" due to his habit of knocking out opponents' teeth. His brutality on the ice lends itself to a negative attitude off the ice. He almost unintentionally ends his relationship with girlfriend Carly (Ashley Judd) after telling her daughter Tess (Destiny Grace Whitlock) that the tooth fairy doesn't exist, and that same night, he is sentenced by head fairy Lily (Julie Andrews) to a stint as the tooth fairy. His new job, complete with a tutu and wings, is not as easy as it looks, and Derek isn't ready to put in the effort to do the job well. With the help of fairy Tracy (Stephen Merchant), he begins to find his way, and is surprised with what he learns about himself in the process.