A beautiful, pure-hearted young woman, Maleficent has an idyllic life growing up in a peaceable forest kingdom, until one day when an invading army threatens the harmony of the land. She rises to be the land's fiercest protector, but she ultimately suffers a ruthless betrayal – an act that begins to turn her heart into stone. Bent on revenge, Maleficent faces an epic battle with the invading King's successor and, as a result, places a curse upon his newborn infant Aurora. As the child grows, Maleficent realizes that Aurora holds the key to peace in the kingdom – and to Maleficent's true happiness as well.

A special bond develops between plus-sized inflatable robot Baymax, and prodigy Hiro Hamada, who team up with a group of friends to form a band of high-tech heroes.