They do so in order to speed up the evolution of mankind, gaining us access to Paradise quicker, sooner. They believe that the justice system is flawed: punishing criminals doesn’t work, it only brings out the worst in them, causing mankind to evolve slower. The fastest way ‘home’ is to wipe them out entirely and have them return in their next life with a clean slate. Soon after Ace is contracted to hunt Adam Brenner, a mass murderer who has just escaped from prison, he experiences a divine intervention, at random, that changes his life forever. Ace learns that he is no better than Adam and is therefore forced to show him mercy, realizing the true way back to Paradise.