The First movie.
Heroes: Superman, Batman, Wonder Woman, Green Latern(Hal Jordan), Flash(Wally West), Martian Manhunter, Black Canary, and Aquaman.
Villains: Darkseid, Kalibak, Lashina, Mad Harriet, Desaad, Steppenwolf, Virman Vundabar, Stompa, Granny Goodness, Gilotina, Bernadeth, Devilance the Pursuer, and thousands of paradenoms and dog soliders.
Supporting: Mera, Lois Lane, Alfred Pennyworth, Jor-El, Quenn Hippolyta, Metron, and Lord Orm a.k.a Ocean Master.
Note to Reader
The reason why I replaced New Genesis with Krypton is because having New Genesis as the planet Apokolips was at war with would take to long. This is a Justice League movie, not a New Gods movie (sadly). The main focus should be the Justice League, Apokolips, and how Earth reacts to the invasion. Another thing is that if Apokolips attacked Earth with New Genesis as the planet keeping Apokolips in check, New Genesis would fight off and protect Earth from his forces. Which means there is no point of a Justice League being formed. Since Krypton was destroyed, this makes the Justice League being Earth's only hope to fight against Darkseid and his armies.
For thousands of years, Krypton and Apokolips have been at war. Krypton is trying to prevent Apokolips' ruler, Darkseid from finding Anti-Life Equation. The Anti-Life Equation allows the person who knows it control over all living things. This was also a personal war, Darkseid has a personal hate for all kryptonians especially Jor-El. Darkseid hates Jor-El for declaring war on him violating his direct order not invade other planets for " a thing that problemy doesn't exist". Darkseid claims that kryptonians are preventing him from "bringing order to the universe". Even though in reality, Darkseid's greatest ambition is to eliminate all
freewill from the universe and re-shape it into his own image. After Krypton exploded, Darkseid terrorized the universe by conquering planet after planet. Darksed became very angry that in all the planets he conquered, there was no signs of the Anti-life-Equation. Then Desaad tells him that kryptonian is still alive and is on the planet Earth. Not only that, it is the son of Jor-El. He also says Earth may be the planet that holds the Anti-Life Equation. Darkseid is hungry for revenge after being hummilated by Krypton for years. He wants pay back for "the sins of his father". Darkseid launches a full scale invasion towards Earth. Darkseid with the Anti-Life Equation to build a new empire and he will start his new empire on Earth by making it the New Apokolips.
J'onn J'onzz a.k.a Martian Manhunter walks across the arid, red sufface of Mars with his head down. He is lonely and depressed because thousands of years ago, Mars had a civil war between the White Martians, and the Green Martians. This wiped out their entire race and J'onn was the only survivor of that war. All of a sudden, he hears a huge boom. He looks up in the sky and sees something that looks a swirling worm hole. He soon realizes it is a boom tube from Apokolips. J'onn is no strangler to Darkseid. Darkseid had once invaded Mars in his mad quest for the Anti-Life Equation, but it failed. J'onn heads toward Earth in a spacecraft of his to warn them of Apokolian invasion.
J'onn with the help from Batman lands Earth mentally contacts Superman, Black Canary, and the Flash to fight off the invasion. However, Darkseid's armies too powerful and have already conquered most the world. J'onn mentally contacts Princess Diana a.k.a Wonder Woman, King Orin a.k.a Aquaman, and air force pilot turned slave Hal Jordan who has just recieved a power ring from a captured Green Latern, Abin Sur. Together they fight off Darkseid forces. In the third act, Superman comfronts a calm and not surpised Darkseid in his newly built palence. Darkseid has been waiting for this for a long time. They braw in a ultimate battle throught throughtout what used to be Metropolis and Superman even tries to throw Darkseid to the sun, but fails. The fight continues until time stops literally when a strange being called Metron offers Flash the ultimate deal with the devil, the Anti-Life Equation. Metron and Flash are the only being that are not paused. Metron tells him that the Anti-Life Equation is actually the only way to kill Darkseid. The arrive at the Source Wall. Metron himself is unwilling or unable to take him any further, and warns Flash that only a "twelfth-level intellect" can survive the attempt to pass it. Flash states that he is overqualified then runs as fast as he through a passage that openis to other side of the wall. Apparently he is correct, as shortly after he appears again on Earth, and in possession of the Anti-Life Equation. Flash offers it to Darkseid. The others yell not to give it. Darkseid has in his hands. However, he soon realizes to his horror that equation's power is far to powerful. Darkseid tries to hold it harder but he feels more pain. Darkseid dies in a blast cause by the Equation. Everyone is amazed. Bruce decides to build a space station over Earth as defense for extraterrestrial attacks. Superman suggests that the league should be permanent and not just protect Earth from extraterrestrial attacks but also other problems as well. Everyone agrees and decide to use the space station as headquters. However, Batman says he has other things to do, but when they need help, "call me and you will"