This week's installment starts with a replay of last season's cliffhanger. Deb points her gun alternately at Dex and LaGuerta in the cargo container, deciding whether to shoot her brother or her boss. Only this time, she kills Dex. (And you thought your sibling rivalry is bad.)
As it turns out, Deb is visualizing this fantasy while visiting the scene of the crime with Vogel, who thinks that Deb is repressing her memories and who's trying to convince her that what she did wasn't bad. "You've forgotten about the life you've saved," Vogel says, referring to our favorite serial killer.
Later, Vogel confers with Dex. She thinks it's better that he continue to keep his distance from Deb. (He hasn't seen her in a week by that point.) She says she's not sure Deb has hit rock-bottom — as we shudder to imagine what that would look like.
So instead, Dex occupies himself with finding the Brain Surgeon. Working down the list of Vogel's former patients, he scopes out a cable guy named A.J. Yates. He notices a huge scar across the back of Yates's head and wonders if Vogel experimented on the dude.
We see that Deb is actually living with Vogel for the time being, volleying between the treadmill and Vogel's laptop — the latter of which she uses to watch footage from Vogel's sessions with Harry — exercising her body and her emotions, clearly.
Dex drops by, and since Deb is there, Vogel takes him outside. She tells him that Yates's scar comes from when he had a lesion removed surgically. So Dex diverts the conversation back to Deb. "You have to get her to forgive me," he implores. "I need her in my life."
Later, he snoops around Yates's house and discovers that the guy has a dad in a retirement home. He also finds women's shoes. (Kinky!) Meanwhile, Yates is chillin' in some secret room inside his own house, watching Dex via surveillance cameras.
Dex, unaware, calls Vogel on speakerphone and talks about Yates, who eavesdrops and then recedes back into his secret lair... in which we see that he has a woman held captive.
Later, the Miami Metro gang grabs drinks to celebrate Quinn's success with the sergeant exam. (By the way, Quinn had success with the sergeant exam.) Quinn overhears a off-duty cop at the bar making a crack about Deb's drunkenness, and he punches the dude. Jamie busts his chops for defending his ex, but she punishes him by being rough in the boudoir. Hey-o!
Vogel lures Deb back to the cargo container with the promise of one beer as a reward. (Poor Deb.) She confronts Deb about why she thinks killing Dex would have been the better choice, getting all up in Deb's grill. Deb has a breakdown, wailing, "How do I make it right?"
"By finally accepting that you're a good person," Vogel says, "who was forced to do a terrible thing. That you made the best of an impossible situation."
Dex runs the prints from the shoes he found in Yates's house — they're all from missing women. Not good, bro. Not good.
Meanwhile, some girl visits Masuka, who characteristically flirts with her immediately. That's when she reveals that she might be his daughter from one of his countless sperm bank donations.
"Oh my god," he says, examining her. "You've got my soulful yet haunting eyes."
They both do the Masuka laugh. Aww, they are related!
Deb and Elway commiserate at their office about their tough dads, their troubled family relations, and about their days as cops. Elway tries to get her to join him in toast, but she refuses the beer. (For once.)
Dex revisits Yates's house. "Vogel says I'm not a monster," he says in voiceover. "But that's exactly the part of me that she's expecting to remove Yates as a threat."
He finds that Yates has scrubbed his house of the damning evidence. He does, however, finds the secret room in the house. Inside, Dex discovers diagrams depicting skull incisions — and concludes that Yates is the Brain Surgeon
Dex finds one of the missing women stuffed in a cabinet — alive. But when he helps her out, her slashed leg gushes blood. Her position in the cabinet had actually been keeping pressure on the wound.
Vogel meets him there later, Dex having dropped off the victim at the ER. They discover that Yates had somehow gotten access to Vogel's patient files. Dexter finds Vogel's notes on him and is irate to read her conclusion that his love for Deb is a delusion.
He accuses her of continuing to experiment on him and of exploiting him for one of her books — and he tells her that once Yates is dead, their relationship will be over.
Back at Vogel's house, Deb breaks into one of Vogel's cabinets and finds more footage from Harry's sessions. In the video, a horrified Harry is recounting having witnessed Dexter's kill room rituals for the first time.
Dex calls Yates under the guise of being a nursing home employee and lures him to his father's room. Realizing Dex has him pinned, though, Yates escapes by pulling his father's breathing tube, setting off an alarm. Better luck next time.
Dex drives back to Miami Metro, thinking (via voiceover) about how his brotherly love for Deb is genuine — while simultaneously ignoring Vogel's calls.
Deb and Quinn talk at the station, and she encourages him to make it work with Jaime. As they part, we see that Dex is watching her. Deb spots him and actually smiles. She and Dexter agree to talk in his car.
On their little joyride, they talk about Vogel and Harry. Deb asks if Harry killed himself, and Dex confirms that he overdosed on heart medication after deciding that Dex was a monster.
"I think I know how he felt — why he killed himself," she says. "But he only got it half-right."
Just then, she reaches over and jerks the steering wheel to the side, sending the car careening off the road and plunging into a lake. An onlooker rescues Deb from the car and take her to shore, but she immediately jumps in again and rescues Dex, betrayed again by her love for him.
On that happy note, that's a wrap for this episode! See you next week!