Watch Injustice (2021) HD Full Movie Free on SolarMovie. Watch Injustice (2021) online free. On an alternate Earth, the Joker tricks Superman into killing Lois Lane, which causes a rampage in t...On an alternate Earth, the Joker tricks Superman into killing Lois Lane, which causes a rampage in the hero. Superman decides to take control of Earth; Batman and his allies will have to attempt to stop him.