Partners with Montoya
Following the murder of Thomas and Martha Wayne, Allen and his partner, Renee Montoya approached Harvey Bullock and offered to take over the case due to its high media profile. Although Bullock might have been inclined to accept their offer at first, he was offended by their arrogance and refused them. At least in their initial dealings, he seems the smoother of the pair, as it is Montoya's tactless remark that decides Bullock against turning over the case. He is then seen when Oswald Cobblepot tells them that Mario Pepper was framed by Fish Mooney and the police, claiming that "poor orphan boy" pricked his conscience, Allen sees through this as a ploy to take over from Mooney.
Allen and Montoya questioned Oswald's mother about her son's disappearance, as he was their source inside Mooney's organization. She's not in a great frame of mind, and when she leaves for a moment, the two of them theorize that Oswald was taken out by Mooney and the cops. Montoya says they won't get away with it so easily, while Allen cautions her not to take things too personally. Mrs. Cobblepot believes that a woman has him in her grasp.
Allen and Montoya went to Mooney's nightclub. The two Major Crimes Unit Detectives questioned Mooney concerning Cobblepot, and Mooney told the two that the rumor on the street was that Jim Gordon pulled the trigger against Cobblepot, turning their investigation to Don Carmine Falcone as the one who had ordered Gordon to kill Cobblepot. Allen and Montoya later visit Gordon and accuse him of having eliminated Cobblepot on behalf of Falcone on the night of September 17.
At the Gotham port, Allen and Montoya manage to get a witness who saw Gordon shoot Oswald Cobblepot and throw his body into the river. Allen and Montoya later arrive, to put Gordon in a cell. The MCU officers accuse Gordon of killing Oswald Cobblepot, though Bullock gives his testimony to try to defend his partner, but this results in Bullock's arrest as well. Despite Jim's objections that he hadn't killed Cobblepot, he isn't believed until Oswald Cobblepot arrives, announcing himself, causing Bullock to lash out at Jim.
Crispus and Renee arrive just in time at the GCPD Headquarters car park to save James Gordon from the hit-man, Victor Zsasz. They take a wounded James to a dissection lab inside a University, where he is treated by Dr. Thawson. After James wakes up from treatment, Crispus and Renee take him to see Bruce Wayne at the Wayne Manor. At the manor, Crispus, who had never met Alfred Pennyworth, is mistaken for a criminal and is intercepted and subdued by the butler. James intervenes, explaining he didn't want to risk a direct approach. Crispus and the others are invited inside, and he and Renee are introduced to Bruce.
- The character was created by Greg Rucka and Shawn Martinbrough and he first appeared in Detective Comics #742 (March 2000). Allen later went on to be one of the main characters in Gotham Central. After his death, he merged with the Spirit of Vengeance, thus becoming the third host of "The Spectre".
- This is the first live-action incarnation of the character Crispus Allen.