Horrible Harry says goodbye in the 30th anniversary finale of a beloved series! The last day of third grade is approaching fast, but a farewell to Room 3B isn´t the only goodbye Doug has to say this year. Song Lee and Mary are busy preparing an end-of-year present for their favorite teacher, Mrs. Flaubert, but their excitement can´t distract Doug from Harry´s suspicious silence. When Harry finally admits that his family is moving to a whole other town, Doug can´t believe his ears. How will he survive fourth grade without his best friend?! But Harry has a more pressing question: who´s that moving in to the empty house across the street from him? And what could these new neighbors mean for their friendship?