In bed, Tom stops kissing Liz when he realizes she isn't into it. She asks for the truth: did Tom have anything to do with the unsolved murder that took place at Angel Station? Claiming he always knew it would end like this, Tom pins Liz to the bed. The people he works for are powerful - did Red tell her about Istanbul - or why she was chosen!? In a cold fury, Tom starts throttling Liz, causing her to bolt up in bed - it's all been a dream, and Tom is as loving as ever. Meanwhile, in an abandoned industrial park, a masked man dumps Seth Nelson in an old refrigerator with an oxygen mask and a couple of O2 tanks. Before closing him in, the masked man takes a photo of Seth with a newspaper as proof of life.
Red has taken up residence in a dusty, book-filled Baltimore ghetto apartment, the former home of his now dead writer friend Frederick Hemstead. He takes a visit from a man in a grey flannel suit, whom we'll call Grey. Red wants him to intercept a package from an Iranian, but there's an impediment: the seller hired the Courier to make the exchange. Red suggests it's time to have the FBI carry the water and puts Liz on the case. The Courier is the perfect middleman. Once he's hired to do a job, he won't stop until it's done, and if either party crosses the other, he kills them both. Of course, Red doesn't know his name, but he does know the Courier intends to deliver a $20 million package to Iranian spy Hamid Souroush at the Winston farmers' market in about three hours.
Liz and Meera follow Souroush through the farmers' market as Ressler tracks them from a surveillance van. Souroush makes contact with a produce seller who shoots him in the head, jumps in an SUV and drives off. Meera and Liz commandeer a pickup and give chase, finally stopping the Courier by ramming his SUV. The Courier limps into an alley with his automatic machine gun; before running out of ammo, he opens a recently stitched wound in his chest and inserts an SD card. When Liz and Meera arrive, they discover that despite the bone sticking out of the Courier's arm, he seems to be impervious to pain.
Back at the post office, Meera and Ressler lay into the Courier - where's the package he was supposed to give Souroush in exchange for the $20 million?! Meera employs painful CIA interrogation techniques, but the Courier merely smiles. Reddington claims he knows nothing, but when Liz points out the Courier's body is covered with scars, Red suggests it's time to call a doctor.
Dr. Pike reports the Courier suffers from congenital anhidrosis - he can feel no physical pain. Moreover, he has several objects buried beneath his scarred flesh. It's not long before Pike pulls the SD car out of the Courier's chest, which reveals Seth's proof of life video, time stamped 04:29 a.m. yesterday. Liz realizes they just stopped Souroush from making a ransom payment. Meera IDs Seth as one of the NSA's best security analysts, worth far more than $20 million. Knowing she needs something to make the Courier talk, Liz visits Red, who demands to know what she discovered about Tom's gun. Liz admits it was used in the classified homicide of Victor Fokin; that's all she knows. After thanking Liz for her honesty, Red contacts a friend who may know the location of the Courier's safe house.
Investigation of the safe house yields the name Tommy Phelps, a dog-eared photo of two little boys and surveillance materials on Souroush and the presumed ransom payer, an unidentified woman. Back at the post office, Cooper dispatches the Courier to Walter Reed to have the rest of the objects dug out of his flesh, prompting him to break his silence. Seth has only 14 hours of air left, and the Courier will divulge his location in exchange for immunity. When Cooper refuses, Liz shows him the photo of the two boys - does the Courier care about his big brother Edgar? Silence.
Red identifies the woman in the Courier's surveillance video as Laurence Dechambou, a former French intelligence operative who now owns a nightclub. Rather than arrest her, Liz hatches a plan. Posing as the Courier, Ressler will tell Laurence the deal is off, instructing her to proceed to the location where she first dropped Seth to pick him up. From there, the FBI hopes they'll be able to find something to lead them to Seth. Liz gets in a surveillance van to coach Ressler through his meeting with Laurence. Unfortunately, Laurence doesn't buy Ressler's act and has her men start shooting at him, so the FBI arrest her instead. Too bad Laurence has no idea of Seth's location.
With time running out, Liz advises Cooper to offer to commute Edgar's sentence in exchange for Seth's location. Cooper orders the prison van containing the Courier to turn around, but he's too late. The Courier has managed to dig a penknife out of his body, murder the driver and escape, abandoning the van near his boyhood home in Woodbridge, Virginia. Red tells Cooper that if he wants to save Seth, he should release Laurence - Red will make her talk. It doesn't take him long to strike a deal: Red will whisk Laurence out of the country, but only in exchange for the location where she dropped Seth.
Meera and Ressler know they've got the right trailer when the Courier starts firing on them with his machine gun. They manage to make it through the door, only to discover the Courier has escaped through a hole in the floor. By the time they reach him, he's dead, having been hit when they returned fire. Back at the office, Liz and Red study a map to deduce Seth's most likely location. With only 30 minutes of air left, Dembe speeds Liz and Red to the industrial park, which is strewn with abandoned refrigerators. Red figures Seth's refrigerator is buried, and they manage to unearth him in the nick of time. In the hubbub of the crime scene, Liz spies Red whispering into Seth's ear...
Back at the post office, Liz takes delivery of an envelope, which contains Victor Fokin's classified file, courtesy of Red. Fokin was a Russian double agent, intending to defect. The most disturbing item in the file is a surveillance photo with a clear shot of Tom. Red tells Grey that Seth gave him the file, and yes, it was a one-time act of gratitude. He could have used Seth to gain earth-shaking intel, but Red's betting on the long play, i.e. Liz. Devastated, Liz returns home, still unaware that two unidentified men are watching her and Tom's every move. And Tom's latest move is a doozy; he's dug up the box of cash, gun and passport and wants to know what the hell's going on.