A newly fostered young boy in search of his mother instead finds unexpected super powers and soon gains a powerful enemy.

Arthur Curry, the human-born heir to the underwater kingdom of Atlantis, goes on a quest to prevent a war between the worlds of ocean and land.

Steppenwolf and his Parademons return after eons to capture Earth. However, Batman seeks the help of Wonder Woman to recruit and assemble Flash, Cyborg and Aquaman to fight the powerful new enemy.