This is a comic series.

Issue 1

A serial killer named Hog gets mutated by Joker, but it results in tragedy.

Issue 2

Black Mask unleashes Hog on Nightwing.

Issue 3

Prometheus attacks Batman for revenge, but Joker interupts it.

Final Issue

Prometheus gets murdered by Joker, but Hog is loose so to save Gotham Batman & The Clown Prince of Crime must team up (the tragedy!) to save the city.