Biochemist Michael Morbius tries to cure himself of a rare blood disease, but he inadvertently infects himself with a form of vampirism instead.
The movie opens with Jared Leto flying to some random cave in the Jungle and luring a bunch of bats out of it. These bats will probably inspire him to wear a costume and put fear into the people and criminals of Gotham City, as the Joker. Oh, wrong franchise.
Travel back in time to a young Michael and his new friend “Milo,” which is what the jaded Morbius calls everyone. Some kids pick on them because they are weak and live in a hospital. Kids can be so cruel. The weirdo hospital / orphanage? director sends Michael away to school and keeps Milo for himself.
This rare blood disease is the worst kind, because Michael grows up to be Jared Leto. A man who can suck the life out of any franchise. Maybe he is sick, maybe he just has histoplasmosis from all the bat guano. Anyways, they kill a rat for sport, and then almost kill a little girl. After that the rat comes back to life, so I guess their evil experiment is a success.