Mister Crowley is a resident of Underworld who can usually be found in either Carol's Place or The Ninth Circle. Crowley was once a part of a group of 5 Mercenarys hired by Allistair Tenpenny, the other four were Dave, Tara, Strayer, and Dukov. They were hired to obtain a unique weapon from Fort Constantine, however during the mission Tara was killed and Dukov locked Crowley in a room full of Feral Ghouls so the reward would only have to be shared between Dave, Dukov and Strayer. Because Crowley is a Ghoul the Feral Ghouls didn't harm him and he managed to escape.
 You Gotta Shoot 'Em in the Head
- Main Article: You Gotta Shoot 'Em in the Head
Crowley now holds a grudge against the remaining survivors of the mission and wants you to kill them and bring back their Fort Constantine keys as proof of there death in this quest.