Greene wants to impress the police force, especially Dexter, and is revealed to have acquired the prosthetic hand from the Ice Truck Killer case, which he mails to Dexter.Debra refuses to yield to pressure to close the case of the overdose death of a prostitute, eventually discovering that Deputy Chief Matthews was present when the woman died.Dexter attends his 20-year high school reunion, hunting his next victim.He begins contemplating the value of religion when Harrison has the chance to attend a Catholic pre-school.Batista's sister Jamie has become Harrison's babysitter, and Dexter and Debra visit a Catholic pre-school in hopes of signing Harrison up.
He operates a body shop where he employs other ex-convicts, to lead them to crime-free lives.
This season features the Doomsday Killers (or DDK), Professor James Gellar and his student Travis Marshall, who seek to bring about the end of the world through killings based on the Book of Revelation.
They leave signs of the Apocalypse including the Alpha and Omega or the Four Horsemen as a cryptic tableau at each crime scene.
Greene claims he made the auction page vanish, but was unable to get the hand back.
La Guerta and Angel Batista have divorced, but try to remain friends; this is further complicated by Matthews' decision to promote Debra Morgan to La Guerta's vacant lieutenant position instead of Batista.