Villains, Vehicles and Plot.
>The main villain is Steppenwolf, an intergalactic conqueror and enforcer for the mighty Darkseid, who is lured to Earth by Lex Luthor's experiments with Kryptonian technology in BATMAN V SUPERMAN: DAWN OF JUSTICE.
>JUSTICE LEAGUE's prologue details how an alliance between Humanity, Atlantis and Themyscira repelled an invasion to Earth masterminded by Darkseid in pre-historic times. During the battle, Darkseid's secret weapon, the Mother Boxes, were left behind and divided between the three realms. A war then erupted between Themyscira and Atlantis, leading both to abandon Humanity.
>Steppenwolf's goal is to retrieve the Mother Boxes, which once united become a powerful weapon capable of subjugating entire worlds. He commands an army of biomechanical insect-like soldiers, the Parademons, who have been kidnapping scientists as part of Steppenwolf's masterplan, which might involve reviving Superman as Darkseid's herald.
>Batman's vehicles include a new, heavily-weaponed Batmobile; a submarine which he uses to journey to Atlantis; the Crawler, a vehicle with mechanical spider legs designed by his father Thomas Wayne to advanced exploration; and the Flying Fox, a cutting-edge supersonic jet that becomes the Justice League's main transportation.
>Batman has set up an alternative base of operations in a high-tech bunker underneath Gotham Iron Works, which is being renovated by Wayne Enterprises. There he conducts research on the escalating meta-human activity across the globe. The bunker will later serve as the Justice League's first base of operations once the team is assembled.
>Alfred will join the final battle, operating the Flying Fox's weapons, including massive assault cannons.
>Gordon will assist the Justice League in investigating the Parademons' activities. He has a minor role.
