After discovering that young Mortimer doesn't have any friends, Oscar helps him start a new club on campus. But the monsters are forced to hide their newfound friendship from the school – and Stuart.

Mortimer and the monsters must figure out how to send Oscar back to his own time, but the only person that can help is the foe of monsters everywhere: a witch. Will they all be able to work together to get Oscar back to Hedgehog?

Frustrated that he doesn't know his magical identity, Oliver convinces Susie to tell him by means of nonviolent protest. Not wanting anyone in her house, Susie takes Oliver on a series of errands to help him figure it out.