In the final season, Debra is a shambles from her guilt. In the finale, Debra is forced to kill an innocent person to preserve Dexter's secret. Hannah McKay also appears, but Dexter ultimately lets her go free. The Ukrainian mob becomes a special nuisance. LaGuerta privately re-opens the Bay Harbor Butcher case. In season seven, Dexter admits to Debra that he is a serial killer. In the season finale, Debra walks in just as Dexter stabs the killer. Season six focuses on the Doomsday killer, who connects his kills to religion. Without knowing their identities, Debra tracks them down but decides they have done the world a service, and lets them go free, sight unseen. Dexter enjoys her company, but at the end she explains she has achieved her goal and will walk away from their relationship. Dexter finds and releases the only victim who lived, and she insists on helping him take down the guilty men. Season five revolves around the Barrel Girl murders. The season ends with the death of a major character. Season four features the Trinity killer, as well as Dexter's exhaustion facing the demands of being a husband and father. As Dexter pursues The Skinner killer, a person discovers Dexter's secret and begins ordering Dexter to kill certain people. Dexter is forced to kill him, but it turns out he is related to a public official. In season three Dexter is ready to kill a target, but is surprised by another man in the house. In the finale, events allow Dexter to frame a dead police department member as the Butcher. He is drawn to a woman who eventually reveals her sinister side. He scrambles to cover his tracks as the department searches for the Bay Harbor Butcher. In season two, the bodies Dexter had been dropping from his boat are discovered. The killer finally reveals their surprising connection, but when he seizes Debra, Dexter has to kill him. Season one features the Ice Truck Killer, who intrigues Dexter personally. Before his death, Harry had also charged Dexter to take care of his stepsister Debra - she is unaware of Dexter's secret and his complete lack of feelings, but they try to be close to each other. In the present, Harry sometimes serves as his mental partner, discussing cases and always reminding him of the code. He creates the steps Dexter must take to keep from being caught. Harry decided to teach Dexter to focus his urges on killing killers who would otherwise escape justice in the legal system. His dead adoptive father Harry, a policeman, created the code after recognizing Dexter's problem when he was very young. As a blood spatter analyst for the Miami police, he has access to crime scenes, picking up clues and checking DNA to confirm a target's guilt before he kills them. Dexter is a serial killer with a 'code' which directs his compulsions to kill only the guilty.The synopsis below may give away important plot points.

Dexter season 7 recap