Dexter is sure that it was Zach Hamilton who killed Norma Rivera but he has no solid evidence to really stand on and begins to follow Zach every chance that he gets. Dexter is therefore completely thrown off when he sees Zach enter Dr. Vogel’s office. Vogel admits that Zach Hamilton is a new patient of hers but refuses to talk to Dexter about his case. Batista is under a lot of pressure from Deputy Chief Tom Matthews about making a final decision on who he is going to promote to Sergeant and won’t get off his back until he makes a decision. When Quinn finds out the disappointing truth that he didn’t get the promotion he kicks it into overdrive to solve the Rivera murder case. With Dexter going along with Quinn, it becomes quite apparent to Dexter that Zach is in the process of stalking his next victim, Sofia Fuentes, a cute waitress who works at the country club at which Zach’s family has a membership. Meanwhile, Deb’s boss is on a hunt to prove that his sister’s boyfriend is cheating on her and is going after other women. Deb agrees to set up a sting operation on the man. Dexter heads out on a date with his next door neighbor Cassie. Masuka unfortunately finds out that his newfound daughter might be experiencing financial problems. Dexter begins to feel light headed and dizzy, and that’s when Hannah walks through the door.
Dr. Vogel tells Dexter that Deb has become quite mortified when she attempted to kill him. Yet now that she has hit her all time low, things will begin to improve. Dexter isn’t that thrilled with Vogel and Deb and puts all his focus into finding A.J. Yates. However Deb and Dexter have another problem on their plate when Yates kidnaps Vogel, so they set out to her rescue. After rescuing Vogel and impaling Yates with a bedpost, she thanks them both for their heroism. The three of them talk about what had happened and Deb begins to accept the situation. At Metro Police, the cops are still trying to figure out just who the monster is that killed Norma Rivera. She had engaged in sexual activity shortly before her death so they assume who ever she had sex with was also the man who ended her life. They have a man in question, her former employer Ed Hamilton, who had admitted to having sex with her but insisted that she was alive the last time he saw her. Dexter begins to wonder if it was Hamilton’s son, Zach, who took her life from her. Vince Masuka finds out that Nikki is in fact his daughter and surely likes the idea of being a father and everything fatherhood has to offer. Quinn on the other hand warns Vince to be careful who he talks to and any “distant” relatives that begin to come out of the woodwork.
The next killer that Dexter goes after on Vogel’s list is a man named A.J. Yates who was placed in a mental health hospital when he was 15 years of age. Vogel tried desperately to channel Yate’s tendencies as much as she had with Dexter yet was unable to do so and ultimately failed in reforming him. When Dexter comes in contact with Yates, he notices a large scar on his forehead. He is later informed by Vogel that Yates had surgery to remove a brain lesion. Dexter breaks into Yate’s house and finds something of interest within Yate’s closet. Dexter is not alone in the house and it looks like he may be the man they are looking for. Dexter also finds something that will put a strain on his relationship with Vogel. Dexter meets a neighbor of Yates, named Cassie. The police have a victim, Norma Rivera, who Dexter believes was killed by someone close to her or by someone that she knew. Angel demands that Quinn, who has passed his exams, get down and solve this murder case if Quinn ever wants to make the Sergeant position in his police career. Masuka gets an unannounced visitor at the police station. Vogel begins her work with Deb trying to help her with her Post Traumatic Stress Disorder and they go and visit the very container in which Deb shot down LaGuerta. It seems as though Deb is making progress, but then doubt sets in.
The Brain Surgeon re-creates the crime scene where he slaughtered Sussman, placing his life less corpse on a meat hook, so that it looks like Sussman blew his brains out with a shotgun. This leads the police to think that it was Sussman who was the Brain Surgeon and killed himself out of repentance. He then sends pieces of Sussman’s brain, the optical portion, to Vogel labeled “His” and “Hers” letting Vogel and Dexter know that he is watching the both of them. Dexter proceeds to go through a list of Vogel’s ex-patients and comes across Ron Galuzzo, who had murdered his best friend when he was a child, but originally convinced Vogel that it was a bully who committed the crime. Yet this turns into a cold lead when they find out that Galuzzo is a cannibal. Meanwhile, Debra gets pulled over for a DUI, but Quinn helps her get out of it. Debra then proceeds to head to the police station with confessing to LaGuerta’s murder. Quinn calls Dexter and tells him what his sister is about to do. He and Vogel make haste to the police station to stop Debra and try to convince her that she is having survivor’s guilt. Dexter finds Debra within the interview room and when she tries to leave to make a public confession, he injects her with M99. Dexter then takes Debra home and asks Vogel to help her with her problems. At the conclusion of the episode, Dexter kills Galuzzo, calling him ‘Disgusting’ for being a man eater, even though he admits that the two of them are quite alike.