Dexter finds that in order to catch the Doomsday Killer, he must create a macabre tableau of his own; Debra's battle with LaGuerta over the case of the dead call girl boils over, and her therapist makes an unnerving suggestion.
Deb and her team are on the yacht surveying Travis's handiwork with Holly and the Wormwood. They find Dorsey's body, as well.
Angel is tied-up over at the Dorsey's place. Travis gives Beth a little pep talk and some final instructions for setting off the poison gas she has in a backpack. She's going to use Angel's keycard to get past security and detonate a device at the station.
Deb calls Quinn and finds out Angel never showed up at the crime scene. He tells her he's headed to the Dorseys', and Deb sends extra back-up there as well.
Deb and Dexter realize that Angel probably ran into Travis.
Beth walks into the station with a backpack. She is able to bypass security. She calls Travis, who says she must get to homicide and Lieutenant Morgan. An officer tells Beth that Deb is in the field and has her wait.
Before Travis can shoot Angel he asks for time to pray. Just prior to pulling the trigger Travis hears Quinn's car pull up out front. Quinn gets inside in time to put out a fire set around Angel. Travis gets away.
Dexter realizes that if he hadn't called in his tip Angel would probably be dead. Deb tells Dexter about Matthews. He tells her to keep an open mind about the situation.
Dexter returns to the station and walks right past Beth. He starts doing some research on Dorsey.
Deb returns to the office and Maria tells her Homeland Security is on its way. Deb is told about Beth and has her sent in.
In the other room Dexter finds a picture of Dorsey and his wife online. He recognizes Beth and sees her walking towards Deb's office. Beth activates her backback and Dexter shoves her into an interview room just as smoke starts pouring from the pack. She starts vomiting blood. Dexter seems to be experiencing some exposure.
Outside a paramedic tells Dexter he should be okay, but could experience side effects over the next few days. He needs to go to the hospital. He tells Deb that "luck" was how he knew Beth was a threat.
To be safe, Dexter gets Jamie and Harrison a room at a hotel.
Dexter tells Harry the next tableau is the "Lake of Fire." It refers to the devil and a war against God. Dexter's nose begins to bleed.
Travis sees on TV that Beth was the only casualty of the Wormwood attack. He mutters to himself that "It's up to me now. My time has come, I must pass the test." He begins drawing on a wall and we see that he is at another home where he has killed a couple.
Deb goes to dinner with Matthews. She tells him what she knows and asks if he was there that night. She says "you can talk to me," and he gives a sob story about being alone after his wife's death. He says the woman OD'd while he was in the bathroom and he tried to revive her. When she died he left. He references their personal history and says he needs a favor. Deb's worried about what to tell the woman's father. Matthews says telling the entire story won't help anyone.
An Agent Hubbard from Homeland Security temporarily takes over the investigation because of a potential terrorist threat. The team hates it.
Deb tells her therapist that Dexter is "all I have." The psychiatrist wonders if her feelings for Dexter are "complex," and more than just brother-sister. Deb is furious at the insinuation. She says she's not "in love with my brother" and leaves.
Dexter had stashed Gellar's hand in the morgue and he gets it back to try and draw out Travis.
Louis is in his apartment with an Ice Truck Killer hand. He draws lines on the palm and seals it into a box. He addresses the box to Dexter.
Dexter's faked tableau is discovered. It's a statue at the museum covered with blood, with 666 on the forehead. Gellar's hand is situated on the statue. Masuka realizes the hand is Gellar's and the cut was made post-mortem.
Travis learns about Dexter's little plan on TV. Dexter sends him a video message saying "the beast is coming for you," while standing in front of his boat. Travis starts furiously painting over a huge piece of art. He's replaced the devil's face with Dexter's.
Matthews is waiting in Deb's office. He is being asked to retire and thinks she ratted him out. She has no idea what he's talking about and says she's done nothing wrong. He's still pissed.
Deb tells Angel and Quinn they've just gotten the case back from Homeland Security and she needs them to step up their game.
Dexter is expecting Travis to come for him on his boat. But he's set-up a kill area on a nearby boat only used a few times a year.
Maria admits to Deb that she was the one who gave up Matthews. Deb is upset she used her to further her career. Maria doesn't care, saying that this is the way the game is played.
Deb tells Dexter her predicament with Maria. They start to playfully joke about chopsticks which leads to Dexter kissing her on the mouth. Deb wakes up and we see this was a dream. She curses.
Travis arrives at Dexter's boat. But as Dexter waits to grab him his nose begins to bleed and he gets light-headed. Travis steals away the hypodermic needle and jams it into Dexter's hand. >Dexter wakes up on a life boat near his boat. He is surrounded by gas cans. Travis pours gas into the water and drops in a match. Flames head towards the tiny vessel as Travis speeds off. Dexter struggles to free himself. Travis looks back and sees the boat explode. But we see that Dexter got free just in time and was able to swim out from underneath the fire.