Dexter is on a mission to find the Trinity Killer because he believes that he is the one responsible for shooting his sister. Meanwhile, Rita finds out Dexter has secretly kept his apartment, Laguerta comes clean to the boss about her relationship with Batista and Quinn's reporter does the department a huge favor.
Big Brother Dexter Wants Vengeance
This week's episode begins when Dexter frantically tries to get through the police tape to see if his sister Deb is OK. "If Deb dies, I'll be lost," he says to himself. Though Deb lost a lot of blood, she's alive and expected to recover. Lundy, on the other hand, is found dead at the scene of the crime.
Dexter is convinced the shooting is the work of Trinity because Lundy disrupted his ritual and the shooter intentionally spared Deb by only shooting her once. Dexter rushes to Lundy's room to get all the notes and tapes he collected on Trinity over the years before they get logged as evidence. His father Harry is with him throughout, telling Dexter he must stop at nothing to get revenge on Trinity, saying, "It's my blood down there too."
Dexter goes through all of Lundy's work on the Trinity case while listening to his dad's two cents every other minute. Dexter waits outside the building where Trinity is expected to strike next, but then Harry tells him that there is one tape missing - the one in Lundy's recorder which has been logged as evidence.
Desperate to hear what's on Lundy's most recent tape, Dexter heads to the evidence room and tells the cop there that Deb lost an important ring and needs to see if it ended up in evidence. As soon as the box of evidence is pulled, Dexter "accidentally" rips his examining glove and asks the cop to grab him a new pair. While the cop steps out, Dexter quickly switches out the tape. Dexter leaves and plays the tape to hear Lundy describing an odd man who bumped into him.
Deb Moves In and Dex's Marriage Is On the Rocks
At the hospital, Deb wakes to find Dexter by her side. She tells him she can't remember much from the shooting, but Dexter keeps grilling her with more questions. Deb gets frustrated with the inquisition, but she tells Dexter that Lundy had a look in his eyes as though he were apologizing.
Anton runs in and is so glad to see Deb is alive. But his relief is cut short when Deb admits she slept with Lundy. Anton says he'll still see her through her recovery, but she tells him not to. He leaves, and Dexter tells Deb she can stay with him and the family.
At the house, Deb notices something is up between Dexter and Rita, and Rita later tells her that she found out Dexter still has his old apartment and didn't tell anyone. Deb is as shocked to hear the news as Rita was when she picked up Dexter's phone and it was Dexter's landlord.
Deb calls Dexter while he's on the way to find Trinity, but he comes to meet his distressed sister at the parking lot where she and Lundy were shot. She begins to yell at Dexter for trying to "throw everything away" and that he needs to make everything right with Rita. She starts to break down saying she's the "broken" one in the family, and Dexter tries to comfort her. "Trinity hurt my sister and I'm going to hurt him back," Dexter says to himself.
Dexter stops at his old apartment before heading out to find Trinity and finds Rita there. She tells him she was worried he was back on drugs or having an affair, so she came in and went through his stuff. She didn't find anything suspicious, but stopped short of breaking the lock on his trunk full of kill tools. Dexter opens it for her and a gun is inside. (Clearly there's a trap door to hide all the scalpels and knives.) He tells Rita it was Harry's gun and didn't feel comfortable having it at home. Rita doesn't buy his lie and calls him out for what a good liar he is. She tells Dexter he should sleep at his bachelor pad and should only come back when he's ready to work on saving their marriage.
Laguerta and Batista Take On the Vacation Murderer
Meanwhile, the department thinks the Vacation Murderer is to blame for Deb and Lundy's shooting. Quinn's girlfriend appears at the crime scene to apologize to Quinn for the Lundy story. Quinn seems to be slowly beginning to forgive her. She tries to get a statement from Batista, and though he declines at first, Batista suddenly realizes he may be able to use the press to his advantage. He tells the reporter to print a story that says Johnny Rose is a suspect and was found in the STD database because he has a severe case of syphilis with multiple partners. His hope is Rose's female partner will see this and the jealousy will turn her against him.
Back at the office, Laguerta tells Batista she Matthews, about their relationship. Laguerta tells him it was a "judgment call" made on her part, but Batista is pissed she made a "call" for both of them. But the next morning, the two make up after Laguerta promises to be honest from now on. Riiight.
Batista's plan to turn the Vacation Murderer's partner against him works, and Johnny Rose winds up shot by his female partner in crime. The police arrive on the scene to find Rose dead and his female partner having an intoxicated fit. Ultimately Quinn takes her down with a Taser. And he thanks his reporter girlfriend with some under-the-covers gratitude.
Despite Batista's brilliant plan to bring down the Vacation Murder, Matthews tells Laguerta that Batista needs to be transferred out of homicide because he doesn't want the district attorney to "make a side show" out their relationship every time they work a case. Guess honesty isn't always the best policy.
Trinity and Dexter Have Something in Common
Throughout Dexter's hunt, Trinity is prepping for the last kill in his cycle. He purchases a hammer at the hardware store and tells the employee he's taken on a new project but must finish it alone.
Trinity poses as a prospective tenant in a building where he made his third kill 30 years ago when it was a tavern. The building's security guard takes him for a tour, and Trinity makes small talk by asking questions, including when the guard makes his rounds, how long they take, if he's a family man, etc.
Dexter arrives and sees that the security guard isn't at the front desk. He realizes he had been so focused on finding out who Trinity is that he forgot about the victim. Dexter rushes into the building, but is surprised when the security guard appears. He stealthily gets by the guard and rushes through the building to try to find Trinity with his victim. We see it's the man who runs the building's coffee counter. The man begs for his life saying he's a father, but Trinity again says, "You made me do this." Dexter then finds the room with surveillance monitors and sees Trinity bashing the man's head in with the hammer.
Determined to follow Trinity to his home and kill him, Dexter and his dad (who wears a seatbelt during the chase despite being already being dead) follow Trinity as he drives away in the van. They go through a seedy part of town and assume that must be where a monster like this hides out. But they end up on a highway and in a suburban town. Trinity pulls into the driveway of a lovely home and walks to the door. Confused, Dexter begins to approach Trinity with his syringe, but the woman who opens the door greats him with a kiss, and children greet him as "dad."
Turns out Trinity isn't the loner that Lundy said he was. "He's like me," Dexter says.
What did you think of this week's episode? Were you expecting the twist at the end?