Carlson Grey is the corrupt warden of Blackgate Penitentiary, where Jim Gordon is sent after being wrongfully convicted for the murder of police officer Carl Pinkney (who was actually murdered by Edward Nygma). After Gordon spends several weeks at the penitentiary, Carlson has him moved into a dangerous wing known as Wing F (AKA "World's End") and is home to the inmates that Gordon had previous locked up, or have some sort of other grudge against him. Carlson reveals himself as the friend of Gillian Loeb, whom was forced out of his job as commissioner due to Gordon several months previously.
Carlson informs a dangerous prisoner, Henry Weaver, that he doesn't want to see Gordon alive by the end of the week. During a movie night, Weaver attacks Gordon with a knife presumably killing him. But this was part of a plot by Harvey Bullock and Carmine Falcone to break Gordon out of prison. When Gordon goes to retrieve fellow prisoner Peter Davies from the infirmary, Carlson corners him intending to shoot and kill Gordon. Carlson is then knocked out by a prison guard named Wilson Bishop, who assists Gordon in his escape, although Wilson requests for Gordon to knock him out so he wouldn't be tied to the breakout.