WARNING: The following article contains spoilers for Man-Bat #1 by Dave Wielgosz, Sumit Kumar, Romulo Fajardo Jr. and Tom Napolitano, on sale now.
Kirk Langstrom has always been addicted to the Man-Bat serum. Though he's consistently made the excuse that he could perfect it one day and finally turning the Man-Bat into a true force for good, it seems that Langstrom is finally running out of time. During perhaps his most destructive rampage ever, Man-Bat is captured by Batman. After running some tests, Batman confirmed that Kirk Langstrom is dying because of the Man-Bat serum and only has a small amount of time left.
In Man-Bat #1, set before Langstrom joined the Justice League Dark, Kirk had once again succumbed to his addiction to the serum. This particular relapse was the worst yet as it seemed to be the final nail in the coffin with his wife Francine, who couldn't stop Kirk from using the formula. But her ire and departure served to only fuel Kirk's delusion that his serum could benefit the world. Wishing to prove that Man-Bat could be a force for good, Kirk took flight and began searching for a crime to stop.
Man-Bat quickly discovered th Blackout Gang robbing a sonic cannon from an unknown source. Man-Bat swooped in, certainly scaring the criminals, but inadvertently triggered a highspeed chase through the streets of Gotham that put many civilians in the crossfire. Not even the arrival of Batman could prevent the inevitable disaster that would follow. The Blackout Gang, desperate to get rid of the winged beast pursuing them, used the weapon against Man-Bat. The resulting struggle destabilized the weapon's core and triggered a massive sonic explosion, knocking Man-Bat out.
When he next woke up, he was in Batman's custody. The Dark Knight explained that after running tests on Kirk he discovered that he had only weeks left to live. But while Kirk would die, Man-Bat would live on. His years of exposure to the Man-Bat serum had mutated his cellular structure, Man-Bat would soon take over Kirk's body completely and Kirk Langstrom's humanity would fade away completely. Kirk refused to accept that, still believing he could perfect the serum, but Batman informed Kirk that the explosion had injured over a hundred people and left those closest to the detonation deaf.
This blow seemed to take the fight out of Kirk. He had originally developed the Man-Bat serum to restore people's hearing but his experiments resulted in the creation of a monster that has terrorized Gotham for years. Now, that very same monster has afflicted people with the condition Kirk himself was trying to reverse. As the saying goes, the road to Hell is paved with good intentions. Kirk Langstrom started out as a promising scientist with a bright future, both professionally and personally. Now, his obsession and addiction have cost him his family, his morality, and soon enough, his life. But perhaps he still has time to do one last good thing before he is taken over by the monster he birthed.