Hackett is a cynical Irishman with a dark sense of humor, who is described to be also loyal and reliable when push comes to shove. Hackett worked for Kovac Defense Services and was sent on a mission to a village in order to keep the residents in place. When some of the villagers tried to escape, he shot more than twenty people. He realized that he doesn't seem to care about shooting innocent people and volunteered to join the "Legion" program, having his memory wiped.