Seven years after the events of Hotel Transylvania, Mavis and her new fiancé Johnny are finally married, with the approval of her father Dracula, and the world becomes aware of (and unfazed by) the existence of monsters. A year later, Mavis reveals to Dracula that she is pregnancy and gives birth to a baby boy named Dennis, who later befriends Wayne the Werewolf's daughter Winnie. Nearing his fifth birthday, Dennis has yet to grow his fangs and Dracula worries that his grandson might not gain vampire powers. Noticing the dangers of Transylvania, Mavis starts to consider raising Dennis in California where Johnny grew up, much to Dracula's disapproval.