An Irish-American, Tommy Monaghan is a Gulf War veteran turned hitman who was resides in Gotham City. He grew up in an orphanage in "The Cauldron" section of Gotham, a predominantly Irish neighborhood. Tommy never knew his father, and the closest thing he ever had was Sean Noonan, the uncle of his childhood friend Pat Noonan.
Monaghan was once working his way up through the ranks of the Gotham City underworld. This all changed when he was bitten by an alien parasite. He found soon after that he had come away from the ordeal with the metahuman abilities of X-ray vision and telepathy. Recognizing the opportunities now open to him, Monaghan began taking contracts on other superhumans.
Hitman was created by the writer Garth Ennis and artist John McCrea. His first appearance was in Demon Annual #2.
Tommy doesn't depend on his meta powers alone for success in his line of work. He makes good use of his sharp mind, military training, and gunfighting skill. Although he is a contract killer, Tommy does have a moral code he lives by. He refuses to kill those who he sees as undeserving of death. Monaghan enjoys being a freelance hitman since it gives him the opportunity to choose his hits. Tommy has no qualms about using his powers to benefit himself, such as reading a woman's mind for what will impress her or undressing her with his X-ray vision. He does have his limits though. An example is the fact that he doesn't use his telepathy to cheat at poker. On the other hand, there was the case where he was invited up to the Justice League of America watchtower to 'audition' for membership and the only reason he accepted the invitation was to use his x-ray vision on Wonder Woman. Upon leaving the watchtower he says, "Now I can die a happy man."
There are some negative side-effects to Monaghan's powers. His eyes are completely black, cornea, iris and pupil. He wears sunglasses frequently to hide this new feature. His meta abilities require some concentration to use and he can come away with headaches and even illness after extended use of them. He has a strong distaste for superheroes and vigilantes, as his respect leans more toward working men with ordinary lives.
He can be extremely cheerful and lively at times, like when he's on a date, but he can be deadly serious as well, such as when he comes face to face with the worst of Gotham's criminals, among them The Joker.
During his superhuman career Tommy was faced with various characters from the DC universe including the likes of Batman, The Joker, Green Lantern, Catwoman. He at times uses outlandish methods to complete his task, such as laying the corpse of a cat on a spotlight to create the "Cat Signal" to attract the attention of Catwoman. His most notable crossover’s come in the form of two of DC Comics "Big Hitters" Superman and Batman. In the story arc regarding Batman (Rage in Arkham pt1), Tommy was contracted to kill the Joker for the sum of one million dollars. Batman confronted Monaghan and ended up shot in the chest at close range (Tommy saw his bulletproof vest). Batman soon caught up with the hitman again and punched him repeatedly in the stomach causing Tommy to regurgitate all over him. Monaghan did successfully shoot the Joker, who survived due to the first-aid skill of caped crusader himself.
It turns out that the whole hit was a trap laid by some otherworldly demons to force Tommy to work for them or destroy him outright if he refused. Together Monaghan and Batman defeat the demons and Tommy escaped before Batman could apprehend him.
With the Superman crossover, the issue took an even more bizarre route. Tommy came upon Superman standing on a Gotham rooftop and they had a talk about life. The discussion was mainly concerning the American public's perception of Superman and the pressure he feels to live up to it.
After their discussion Superman flew back to Metropolis feeling his burdens of guilt and self doubt relieved. Once Superman was gone, Tommy commented aloud, "What an unbelievably cool guy." He then took out a sniper rifle and aimed it across the street, finishing his hit on a local criminal. Tommy then holstered the rifle and left the rooftop on the phone with his friend Nat to tell him who he bumped into.
Most of the Hitman comics revolve around the same theme, a look into the darker side of DC Comics.
Tommy's career and life end when dies in a battle with Truman. He dies in the skirmish along with his friend Nat Walls.
His weapons of choice are a pair of Colt M1911's. He has said he prefers automatics because of the amount of bullets they contain. His back up firearm is a rather cumbersome Smith Wesson M29, which he calls the, "Dirty Harry gun". He likes this gun for its power and reliability.