The homicide division is handed an unbelievable lead when the Ice Truck Killer's latest victim is found alive but mutilated; Dexter is on the trail of a person who traffics in humans.

The squad identifies the Ice Truck Killer; Rita's ex-husband, an abusive addict, is paroled.

Dexter appears to be connected to a psychiatrist suspected of murdering a suicidal patient.

While on a weekend getaway with Rita, his sister and her new beau, Dexter learns that his biological father, thought to be dead for 30 years, has just passed away, and that he's willed his son everything he owned.

The Ice Truck Killer prepares a crime scene for Dexter: a hotel room all covered in his previous victim's blood. But Dexter does not appreciate this gift, because his childhood memories hunt him.

The Ice Truck Killer sets a trap for Dexter by kidnapping someone close to him; Dexter's increasingly odd behavior piques Doakes's interest.