As Stitch, a runaway genetic experiment from a faraway planet, wreaks havoc on the Hawaiian Islands, he becomes the mischievous adopted alien "puppy" of an independent little girl named Lilo and learns about loyalty, friendship, and ʻohana, the Hawaiian tradition of family.

Five years have passed since Hiccup and Toothless united the dragons and Vikings of Berk. Now, they spend their time charting unmapped territories. During one of their adventures, the pair discover a secret cave that houses hundreds of wild dragons -- and a mysterious dragon rider who turns out to be Hiccup's mother, Valka. Hiccup and Toothless then find themselves at the center of a battle to protect Berk from a power-hungry warrior named Drago.

As Hiccup fulfills his dream of creating a peaceful dragon utopia, Toothless’ discovery of an untamed, elusive mate draws the Night Fury away. When danger mounts at home and Hiccup’s reign as village chief is tested, both dragon and rider must make impossible decisions to save their kind.

On the rugged isle of Berk, where Vikings and dragons have been bitter enemies for generations, Hiccup stands apart, defying centuries of tradition when he befriends Toothless, a feared Night Fury dragon. Their unlikely bond reveals the true nature of dragons, challenging the very foundations of Viking society.