A nuclear submarine is attacked near the Marianas Trench. Then, we go to Cyborg, who is having dreams of still being human. He's still having a hard time
adapting to his situation. Colonel Trevor, their liasson with the government, is the one who has picked the team's name, "The Justice League". In Greece, Superman an Wonder Woman are clearly a couple. Arthur Curry, who has recently buried his father, is drunk at a bar and gets into a fight over saving a lobster. We see has gills and superhuman strength. A guy tries to stab him and his knife shatters. We can guess who Arthur really is...
Cyborg investigates the sunken sub and is attacked by creatures. He calls a meeting of the group, who investigate.
The Queen of Atlantis wants her long lost son, Arthur, to inherit her throne, not her other son, who is evil.
The stories converge and Arthur takes his rightful place in Atlantis.
I liked this animated movie better than the first "New 52" Justice League Film because it wasn't just an origin story, though I'm still undecided if
I really like this revised versions of the characters...