Several years have passed since the events of the previous story. Hiccup has grown from a socially awkward young boy, to becoming his own man. Yearning to see the world, while his father urges him to take over his legacy. Caught between his own desires, and the weight of obligation. However, things take an interesting turn, when Hiccup and dragon are forced take on a sinister new threat that plans to destroy everything they hold dear.

After officially retiring from being a supervillain, Gru enjoys his day as a single father of his three adopted girls. However, when a new super villain shows up, the anti villain league recruits Gru to help stop him.