The Kingdom Hearts video game series, developed by Square Enix in collaboration with Disney, is set in a universe consisting of numerous self-contained worlds based on intellectual properties from both companies. Most worlds are based on different Disney films, although several original worlds appear throughout the series.

The series centers on the character Sora, a boy who searches for his lost friends and encounters Disney and Square Enix characters as he travels between worlds. In the first game, Kingdom Hearts, Sora fights against the villains of the series known as the Heartless and seals each world he visits to prevent their return. In Kingdom Hearts II, Sora helps the residents of these worlds again while searching for his friend Riku. The Kingdom Hearts games have been both critically acclaimed and commercially successful, and the design of the worlds has been praised for its faithfulness to the source material.