Mouton meets Gazali in London and helps him interrogate one of the surviving members of the "Gulls" hoodie gang. Mouton adopts the guise of "Amir", a Middle Eastern mercenary working for the Petrov brothers, the cover identities used by Gaz and Craig. The teenaged gang member, Sam, tells what he knows of the Firm's operation at the East End laundromat, including the fact that he is friends with one of the thugs who frequently guards the basement.

The team is able to capture the thug (known as "Stoney") and drug him with truth serum, discovering more details about the basement and its contents. These include a blood bank similar to the one found at the Hamburg brothel and cages holding several captive women who were illegally smuggled into the UK. The Professor offers to help Stoney with his sickly mother in exchange for turning traitor, then arranges for Reggie Staunton to assist in the upcoming raid. 

Reggie and Stoney escort Mouton and Gaz to the Flop 'n' Fold laundromat at around 3 in the morning, claiming to have captured the men as a result of their part in the attack on the Gulls. They are met by Ham Porfrey, the current head of the Firm, and several other henchmen who serve the Cockney gangster. As Ham tries to learn more about Gaz and Mouton, Gaz is recognized by another person in the basement, a man named Leithauser. Gaz simultaneously recognizes Leithauser as one of the missing members of his old SAS squad, realizing he's been turned by the vampires.

With their cover blown, Mouton removes his false restraints, draws a gun and opens fire, killing Ham with a single bullet to the head. Gaz stabs a thug with his knife and Reggie and Stoney help take out the other surprised Firm gunmen. Leithauser takes a bullet to his kneecap but doesn't seem to be terribly bothered by it, indicating that he's been given some inhuman abilities by his new masters. He blazes away with a handgun, killing both Reggie and Stoney in the blink of an eye, then grabs a surviving Firm shooter as a human shield. 

Listening to the events in the basement from inside of a surveillance van, Craig readies an explosive-laden remote control car. Telling Sam (also in the van) to be prepared for a fast getaway, he pilots the RC car to the basement level and then alerts Gaz and Mouton to its approach. Gaz is able to take cover before the car is detonated, spraying shrapnel into Leithauser and the man he has grappled. Both men are killed by the explosion, and Mouton receives minor injuries due to his proximity. 

Gaz kicks in a metal door and finds the pens where four malnourished women are being kept like some sort of cattle. The team frees the women and then raids the room for intel. The Professor takes several blood vials from the cold storage containers inside, and Mouton grabs an assortment of equipment and a laptop for later examination. Gaz searches the smoking body of his former buddy and finds a thick wad of cash and a smartphone. Once the place is cleared out, the former Legionnaire sets up some explosives and thermite grenades to destroy the remaining blood and the rest of the basement. 

The team escorts the exhausted women to the van and they leave as Mouton's bomb goes off, flash-frying the contents of the basement and dealing another blow to the ABC Conspiracy. Evading the police responding to the scene, they head out of the East End. Gaz uses the phone he pulled off of Leithauser, calling up Muir and taunting him about the destruction of the blood bank. Muir asks if Gaz has destroyed all of the blood, then agrees to a meeting in an industrial dockyard on the Thames. Muir suggests that Gaz doesn't bring too many people to the meet. Mouton makes a call to arrange for access to a Barret .50 sniper rifle...