FIRST MOVIE - Batman, Superman, Wonder Woman, Green Lantern, Aquaman, The Flash and Cyborg are all already established heros but have not come together yet. Cyborg is the only one who isnt established and becomes a superhero this movie. As Steppenwolf tries to invade, Batman begins to form this team to protect the earth from the attack. They defeat and kill Steppenwolf and in his last words he says, "ALL HAIL DARKSEID". The Justice League then become a proper organisation and become the defenders of earth.
The first end credit scene shows J'onn J'onzz finding Clark Kent and revealing to him that he knows hes Superman, Clark gets shocked and then J'onn shapeshifts into the Martian Manhunter and it ends there.
The second end credit scene shows Desaad talking to someone sitting on the throne but with his back facing Desaad, the final shot shows Darkseids eye then ends there.
