Over a year has passed since Lumen Pierce entered, and shortly left, Dexter Morgan's life. He has moved on and is raising his son with the help of a new nanny. Dexter begins looking for a set of principles to pass onto his growing son, Harrison. In dealing with a target who has a Jesus tattoo, Dexter questions if religion is the system he wants to bring into his son's life. He asks his friend, Angel Batista, about his beliefs and Angel recommends a religious school. Soon, Dexter becomes involved with the religious characters, Brother Sam (who believes that religion is beneficial), and Travis Marshall (who demonstrates the harmful effects of faith). As the religious beliefs of others intrude into his life, Dexter is faced with dangerous challenges. In addition, Dexter's relationship with his adoptive sister, Debra Morgan, is put on the line as she comes closer to discovering his true nature.
There is not a Big Bad, such as for every Season before it, but the major villains tie into the story effectively in a unique fashion.The antagonistic side of the story falls on a series murders placed on Miami's doorstep. The man responsible for them is dubbed The Doomsday Killer based on how the crime scenes are actually religious "tableaus" deliberately created to supposedly bring on the End of Days.
Professor James Gellar - A university teacher of religious arts. Originally thought to be the Doomsday Killer, he is later revealed to be deceased..
Lisa Marshall - Sister to Travis, she is an elementary school teacher.
Jamie Batista - Sister to Angel Batista, she is a Latina in her mid-20's, relocating to Miami for her grad school while taking up a job as Nanny for Harrison Morgan.
Mike Anderson - an African-American detective from Chicago, with fairly similar traits to James Doakes.
