Another really solid episode, with a lot of stuff in play and just about all of it being at least a potential problem for Dexter. Picking up where we left off, Deb literally flees from Dexter's apartment to go vomit, which is considerate of her. After catching her, Dexter at least does not hold anything back, confessing that he's been a serial killer since he was 20, that he's the Bay Harbor Butcher -- and that Harry gave him his code. Back in the apartment, Deb points out that horrible things happen to people and they still don't turn out to be serial killers, but Dexter tries to make her understand, even using the words "Dark Passenger," and I'll save Deb's reaction for the full recap but it's pretty great. They have a philosophical argument about whether it's okay to kill when the justice system fails, and Deb wonders what she's supposed to do now, but she does come up with the stopgap measure of punching Dexter in the face.

Deb reads back on some of Keith Carradine's writings, which tell her that serial killers have an addiction, and will continue to kill until they're caught. Instead of turning him in, though, as is her strong first instinct, she offers Dexter a form of rehab -- he'll move in with her and she'll watch him 24/7 to make sure he never kills. Dexter is not too optimistic about the potential efficacy of this plan, but agrees to it. Deb is not kidding around, even sleeping in her living room so she'll always be between Dexter and the door and telling Dexter he's going to have to be completely honest with her. But she also tries to get Dexter to explain how it feels to be him, and Dexter responds by telling her in detail about his relationship with blood, which maybe suggests that this wasn't the best dinnertime question. He does promise, though, that he'll tell her when he gets the urge to kill.

LaGuerta goes rogue in confirming that the blood on the slide she found belonged to Colin Hanks, thus confirming her suspicion that the Bay Harbor Butcher is still at large. She's surely doing this as much to try to exonerate her friend Doakes as to find the real killer, but whatever her motivations, this isn't good for Dexter.

In Ukrainian news, Batista and Quinn go back and shut down Jason Gedrick again; while Gedrick takes Batista to his office, Quinn works on a blonde girl named Nadia, who tells him that Soroka was dating one of the bouncers there -- the same guy Batista learns hasn't been to work since the night Soroka disappeared. Quinn and Batista haul him in, and it doesn't take long for him to give up Viktor's name, which, given that he killed him, could bring Dexter into this plotline as well. Jason Gedrick's problems don't end there, as Isaak Pullo shows up in his office and menacingly wonders if someone in "The Brotherhood" decided to get rid of Viktor without his approval. Jason Gedrick swears that didn't happen, which is good news for his continued existence, if the sinister visit Isaak Pullo pays the bouncer is any indication. Nadia, however, calls Quinn, and although she doesn't yet give up any further information, she does appear to be interested in, um, keeping their dialogue open.

When he has time to consider it, Dexter wonders how the Ice Truck Killer hand came to be in his apartment. While he's checking on it in the evidence room, Masuka comes in and confesses what happened with The Horrific Nightmare of an Intern and Greene, and Dexter immediately suspects Greene is the one that kept it. He resolves to get closer to Greene, and uses a work assignment to check out Greene's place -- and via a video diary discovers that Greene has it in for him, and has been ruthless with his enemies in the past. With Dexter in the place, Greene unexpectedly comes home, and Dexter attacks him physically, but even though Greene fakes being a total pussy about the whole thing, he's going to be a problem, and Dexter knows it. When Greene shows up at his place and flaunts how unafraid of Dexter he is, Dexter resolves to kill him, and drugs Deb's food and then Greene. But, remembering what he promised Deb, he calls her and comes clean, saying he's a monster and she should arrest him. In a reversal, however, Deb takes the fact that he didn't go through with the murder as a positive sign, and declares that neither of them is going to give up on him. Dexter's left with the issue of how he's going to get Greene out of his life without killing him, but that momentarily seems like a smaller problem to have. However, in the end, the killer with whom Dexter bonded spectacularly offs himself, showing Dexter he never changed -- he just wanted a couple days in the sun before he ended his life. I still think it could fall apart at any point, but this is two episodes in a row of a show I actually want to watch.