Agony — E. Michael Lewis

I did it because they deserved it. I did it because I deserved it.

Thomas “Agony” Agonetti: torturer, rapist, serial killer, executed by the state for his crimes. They say his ghost haunts his old stalking grounds, the decaying Twin Lakes Mall. Trevor Westmoreland, a security guard with some imagination, agrees to work the night shift, cruising in circles through vast empty parking lots, warding off trouble. But when a shopper who was Agony's type disappears, followed by another security guard, the stories of the ghost seem all too real. Now Trevor must do what the police never could: find Agony's hidden torture chamber and put an end to his killing streak, once and for all.