|REAL NAME: Kirk Langstrom
Kirk Langstrom is a scientist who has studied bats for most of his life. His ongoing research into their techniques and behaviour has led him to the conclusion that they are the ultimate survivors and will be the only creatures that will survive the next evolution.
Langstrom became so obsessed with his findings that he began to experiment and created a serum which would transform him into a bat.
Though Batman has clashed with him several times and changed him back into a human. Langstrom's battle with his inner demons leads to suggest that he may one day take the serum and transform again.
-On two occasions Kirk's wife Francine has also take the serum and transformed into a giant bat (She was called She-Bat) once was accidental (Similar to the animated episode "Terror in the sky") and the other she voluntarily took it because she felt that it would bring her closer to Kirk.