Dexter investigates who shot Brother Sam. Meanwhile, Homicide interrogates the woman who Quinn slept with who is involved in the Doomsday Killer case.
With the help of his newfound friend Brother Sam, Dexter wonders if there is light within him to counter the darkness, while the search for the Doomsday Killers takes him in a new direction; Batista and Quinn pay a visit to the university where Professor Gellar taught; due to departmental regulations following the shooting, Debra is forced to begin therapy.moreless
The team investigates murders that have a religious undertone to them.
Dexter faces a serial killer from his past; Debra has problems with her new position and Travis with Gellar think of their next move.
In order to solve the mysterious murders, Homicide asks for the help of Brother Sam, who Dexter knows used to be a serial killer. Debra has two proposals, one personal and one job-related.moreless