It's now 6 months since Captain LaGuerta's death. Dexter is still working as a blood spatter expert but Deb has quit the force and is now working as a private investigator. She's also been avoiding Dexter as much as possible. Angel Batista is now the squad's Lieutenant and Tom Matthews is a Deputy Chief. Dexter is worried about Deb in general but even more so after he hears she hasn't been in touch with her new boss for two weeks. Metro homicide has a new case after a body is found on the beach. The man's skull has been sliced open and a small part of his brain removed. Matthews introduces a civilian expert, Dr. Evelyn Vogel, who has volunteered her time to help with the investigation. Dexter is distrustful of her from the outset and with good reason as it turns out: she seems to know a great deal about him. Written by garykmcd

Dr. Vogel shows Dexter some video she shot when his father Harry visited her for help in treating him. Dexter was only 10 years old when Harry first visited her and she takes more than just a little of the credit for what Dexter calls Harry's code: that he would only kill bad people. Vogel says she did it because she cared for him. Having saved his life, she now wants to call in a favor: she thinks the man who recently sliced open someone's brain and left the body on the beach is one of her former patients. She wants Dexter to do what she and Harry taught him to do. Deb's boss meanwhile isn't too keen that she put herself at risk in trying to recover the jewels from Briggs. She's not done yet, convinced that Briggs kept the jewels in a storage facility. She gets more than she bargained for. The police find another body with his skull and brain sliced open. Dexter finds a fingerprint leading him to a man named Sussman, who hasn't been seen for a few weeks. Written by garykmcd

Deb is going through a particularly bad patch and there is nothing Dexter can seemingly do about it. A cop finds her behind the wheel of her car, drunk. She had the good sense to pull over but ran over a parking meter in the process. She contacts Quinn who manages to get her out without being charged. Dexter blames himself but Vogel says he shouldn't take on her problems. She also wonders why Dexter didn't kill her when she found out about him. Drunk again, Deb goes to the station and tells Quinn she killed LaGuerta. Meanwhile, Dexter and the police check out Lyle Sussman's cabin only to find him dead on the floor, the victim of a shotgun blast through the mouth. Dexter is wondering if he was the real killer or if someone else was manipulating him; perhaps that someone also killed him. As far as the police are concerned however, the Brain Surgeon case is officially closed. Vogel continues to receive threatening messages, this time two package with brain matter labeled his and hers. ... Written by garykmcd

The next potential killer on Vogel's list is A.J. Yates, who was institutionalized at 15. Vogel tried to channel his hostilities much as she did with Dexter but was unable to do so. When Dexter sees a huge scar on his head, he learns from Vogel that Yates had surgery to remove a brain lesion. He breaks into Yates' house and finds something interesting in the closet. Dexter isn't alone in the house however and it looks he may be their man. He also finds something that affects his relationship with Vogel. Dexter meets a neighbor, Cassie, from the next door apartment. The police have a murder victim, Norma Rivera, who Dexter believes was killed by someone she knew. Angel presses Quinn, who has passed his exams, to solve the case if he hope to make sergeant. Masuka gets a surprise visitor at the station. Dr. Vogel begins working with Deb and they visit the container where she shot LaGuerta. She seems to be making progress but doubt sets in and she decides to do something about it. Written by garykmcd

Dr. Vogel tells Dexter that Deb was traumatized when she tried to kill him. Now that she's hit rock bottom, things will improve. Dexter isn't too happy with either Vogel or Deb and concentrates on finding serial killer A.J. Yates. Deb and Dexter have another problem when Yates kidnaps Vogel and they set out to rescue her. At the station, the police continue investigating the death of Norma Rivera. She had sex not long before dying and they assume that whoever that was is also the man who killed her. They have a suspect, her former employer Ed Hamilton, who admits to having had sex with her but insists she was alive when he last saw her. Dexter wonders if Hamilton's son Zach might have been involved. Vince Masuka meanwhile has confirmed that Nikki is his daughter and is quite taken by the idea of fatherhood. Quinn warns him to be careful about relatives who appear out of nowhere. Written by garykmcd

Dexter is convinced that Zack Hamilton killed Norma Rivera but has no proof and takes to following him whenever he can. He's more than a bit surprised to follow him to Dr. Vogel's office. She admits that Zach is a new patient but refuses to talk about his case. Batista is under pressure from Deputy Chief Tom Matthews to make a decision on who to promote to sergeant. When Quinn learns he didn't get the job, he redoubles his effort to solve the Rivera murder. With Dexter tagging along, it becomes obvious - to Dexter at least - that Zack is stalking his next victim, Sofia Fuentes a waitress at a yacht club owned by the Hamilton family. Deb's boss wants to get evidence that his sister's boyfriend is a skirt-chaser who sees other women. Deb agrees to try and lure him into a compromising situation. Dexter goes out on a date with his new neighbor Cassie. Masuka learns that his newfound daughter may have serious financial problems. Dexter gets a surprise visitor. Written by garykmcd

After being drugged by Hannah McKay, Dexter wakes up in an industrial area outside of town. He knows that Hannah is responsible and she's surprisingly easy to find, which makes Dexter more than just a bit suspicious. It turns out she's living on a luxury yacht with her husband Jacob. She's changed her name to Maggie and says she's quite happy. Her husband doesn't appreciate the fact that she's met with Dexter forcing her to take action and for Dexter to help her out. Meanwhile, Dexter has agreed to teach Zach Hamilton the code - to Dr. Vogel's delight - but he is proving to be a difficult student. When someone close to Dexter is killed, he's certain that Zach is the culprit. Masuka arranges a new job for his newfound daughter. Written by garykmcd

Dexter is certain that Zach Hamilton killed his next door neighbor Cassie, who is found bludgeoned to death in her apartment. The scene suggests that the crime was impulsive rather than planned, as was the case with the death of Norma Rivera. Dexter finds Zach's blood under her fingernails but can't report it for obvious reasons. Zach is in the Keys - he's used his credit card - and Dexter and Hannah set off to find him. What he finds there impresses Dexter but also suggests that Zach isn't the killer. Meanwhile, Dexter is also helping Hannah acquire a new identity and make arrangements to leave the country. There is a strong bond between them however and Dexter begins to see a different future for himself. Written by garykmcd

Dexter has decided to make a new life for himself with Hannah and Harrison but not before he takes care of the Brain Surgeon. In searching Zach Hamilton's photo studio he finds a clump of hair and blood hidden under a table. When Dexter runs the sample against the DNA database he finds a familial match - to Dr. Evelyn Vogel. Somewhat incredulous at his revelation, Vogel explains that she once had two sons, the eldest of which killed the other. He was placed in a mental institution but died in fire. Dexter believes he must have survived and soon has him identified. Deb meanwhile is having second thoughts about returning to Miami Metro. She's also agreed to let Hannah, who is now being sought by a Federal Marshall, hide out at her house. Written by garykmcd

Having made the decision that he and Harrison will move to Argentina with Hannah, Dexter has a lot to do. He tells Deb about his plan but that doesn't go over very well. He also tells Dr, Vogel that her son, Saxon, is dangerous and she is in need of protection. She insists that he back off and let her deal with him in her own way but Dexter has no intention of leaving Miami while Saxon is alive. Saxon has problems however and he takes his mother to his killing room explaining that it's identical to the treatment room at the mental hospital she put him in. He wants his mother to help him in the same way she helped Dexter. Meanwhile, Quinn suggests to Jamie that she should at least attend a job interview for a position at a prestigious academy in Atlanta. Masuka is upset when his daughter Niki shows up high at a crime scene. Written by garykmcd

Still coming to terms with Dr. Vogel's death, Dexter wants to eliminate Oliver Saxon before he, Harrison and Hannah head off to South America. He also has a lot of personal items to tie up including selling his condo. Saxon shows up as a prospective buyer and offers Dexter a deal: they stop going after each other and go their own way. Dexter is non-committal and, having located his kill room, sets a trap for him. Meanwhile, U.S. Deputy Marshall Clayton is following Deb, certain that she will lead him to Hannah. Dexter is continuing to reevaluate his priorities and his final choices have an impact on several key players. Written by garykmcd

Dexter has to act quickly when Hannah tells him Elway is staking out the airport. He finds a way to get him out of the way but it also leads to the entire airport being closed. With a hurricane bearing down on Miami, few options are open to them. Dexter races to the hospital when he learns that Deb has been shot. She seems to be recovering and he decides to send Hannah and Harrison to Jacksonville where they could catch a flight. A return trip to the hospital leads to Saxon's arrest but also bad news about Deb. Realizing that he has, directly or indirectly, been responsible for the death of everyone he's ever loved, Dexter accepts there is only one option open to him. Written by garykmcd