After the devastating events of Avengers: Infinity War, the universe is in ruins due to the efforts of the Mad Titan, Thanos. With the help of remaining allies, the Avengers must assemble once more in order to undo Thanos' actions and restore order to the universe once and for all, no matter what consequences may be in store.

Fuelled by his restored faith in humanity and inspired by Superman's selfless act, Bruce Wayne and Diana Prince assemble a team of metahumans consisting of Barry Allen, Arthur Curry and Victor Stone to face the catastrophic threat of Steppenwolf and the Parademons who are on the hunt for three Mother Boxes on Earth.

A boy is given the ability to become an adult superhero in times of need with a single magic word.