In the extremely funny and violent fourth volume of the HITMAN series, Tommy Monaghan's past comes back to haunt him once again. Angered by Tommy's previous attack against them, the Arkannone, a cabal of creatures residing in Hell, send the 10-foot tall skeletal demon Mawzir on a mission of revenge. Realizing that his X-ray vision and telepathy are no match for the six-armed, artillery-toting hell spawn, Hitman sends Catwoman and Etrigan the Demon on a quest to hell to retrieve the one weapon that can stop Mawzir, the gun known as the "Ace of Killers." But can a man who is paid to trust a cat burglar and a duplicitous demon escape with his life?