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Previously on Mi-5
With Harry (Peter Firth) detained in a secret detention facility, the rest of the MI-5 team must come together in a time of grief and chaos to stop a band of conspirators from taking over the country. For more, read the full episode recap here.
This Week's Episode: "The Cell"
As a part of Operation Waterfall, Zaf (Raza Jaffrey) has infiltrated a local Al Qaeda cell with instructions to turn one of its members into an informant. Living with the cell's henchman in a council estate far from the center of the city, he witnesses firsthand a power struggle between his "colleagues" Mustafa (Ofo Uhiara), Samir (Adhir Kalyan), and their leader Hanif (Aaron Neil). Testing out their resolve by forcing them to murder an innocent environmental health officer, Hanif decides that it is Mustafa who will lead the way for their next attack, which is set to go into action the second they get their hands on a thermobaric bomb.
Returning to headquarters, Zaf relays the information on the impending attack. Such a bomb would destroy the entire city, and Mi-5 cannot take any chances and must stop the bomb as soon as possible. Adam (Rupert Penry-Jones) suggestion: buy the bomb themselves. Since there's only one of two of such bombs floating around the world, it should be easy to locate a buyer. While Ruth (Nicola Walker) tracks down potential leads, Jo (Miranda Raison) brings new hire Ros Myers (Hermione Norris) up to speed on their best chance to turn a cell member: Mustafa, born Michael Johnson, a petty criminal who found Islam in prison, broke up with his fiancée, and joined the cell. But Ros, a former Mi-6 associate, is already several steps ahead of Jo, and her snippy, snarky attitude begins rubbing people the wrong way. But as she was vital in stopping her powerful ambassador father and his corporate conspirators from committing terrorist attacks, Mi-5 knows that she is vital to their organization.
After making contact with Mustafa/Michael's former fiancée Leigh Bennett (Joanna Horton) and informs her of the situation, Ros makes a secret rendezvous with Zaf, advising him to play to Mustafa/Michael's emotions. If they can remind him of Leigh and how his actions could bring about her death, maybe he would turn informant.
On the lighter side of things, goaded on by the hospital-trapped Juliet Shaw (Anna Chancellor), Harry does one of the most difficult things in his life--he asks Ruth out on a date. Flattered, she agrees, and they have a wonderful dinner together and discuss a potential future of travel and museum visits. Unfortunately, Ruth learns that the rest of the team has found out, and as to not risk undermining Harry's credibility among the staff, she breaks things off for good.
At the dirty, lowdown council estate, Zaf strikes up a conversation with Samir, planting seeds of doubt in Mustafa's impending leadership. But this is all a ploy to do some investigating, and when Zaf secretly blows a fuse in the microwave and Samir goes out to find a replacement, Zaf takes to Mustafa's room looking for anything that could help him in his mission. Just then, Mustafa returns to their flat, but does not catch Zaf doing anything wrong.
Meanwhile, the very stern and intimidating Ros has filled Leigh in on the details of Mustafa/Michael's actions, and when she mentions that the tabloids will have a field day with her should the bomb go off, Leigh is forced to aid Mi-5. Appealing to Leigh's still-burning love for her childhood sweetheart, Ros manages to have Leigh "run into" Mustafa/Michael in line at a government building. Taking their conversation outside, Mustafa/Michael defends his new religious convictions much to the chagrin of the woman who still loves him. But her angry routine is, as Ros puts it, quite alluring, and the terrorist hands her his number and says to call whenever.
Back at Mi-5, Ruth has intercepted an e-mail coming out of Kenya from two Saudi businessmen to Hanif Ibrahim. This must be about the bomb. It seems that the businessmen were in Kenya meeting with a man named Iain Kallis (Larry Lamb). Kallis used to be an agent during the apartheid years in South Africa, but now is an arms dealer to a front company called Protech Holdings. And wouldn't you know it, he's on his way to London for the arms fair and staying at the Royal Heights Hotel for a week. Adam and Jo's mission? Go undercover and help convince him to overthrow a foreign government and get it on tape, thanks to a bug Malcolm (Hugh Simon) plants on Jo's collar.
At the council estate, Mustafa/Michael gets a call from Leigh (with Mi-5 listening in), and they agree to meet at a café. Wondering what has happened to her former lover and calling him out on being brainwashed while in the clink, she nonetheless convinces him to bring her back to his secret flat. There, they embrace and reignite their passion.
Adam and Jo arrive at the Royal Heights Hotel, posing as arms dealer Sam Hunter and his associate Gill Turner. In order to overthrow the government in question, "Sam" must get his hands on a thermobaric bomb and Kallis is the man to do it. He already has a deal in place with somebody else, but "Sam" raises the offer by 10%. Okay, says Kallis, but first "Gill" must accompany him to a play that night as his date. Post-play, Kallis brings Jo back to his hotel room and agrees to the deal so long as she and "Sam" put up a down payment. But when Jo tries to leave, he calls her terrible names and slaps him around, apparently par for the course in re: his sadistic sexual ways. A trained spy, Jo and Kallis are mostly evenly matched until he attains the upper hand. Just then, Adam and Ros bust into the room and stop the violence, threatening him with the audio recording of their meeting.
Now under interrogation, Kallis finally admits that the type of bomb they're looking for has already been bought by the Saudis and he was just a middleman. Reasoning through the timeline, Mi-5 realizes that the bomb must be arriving on the UK shores any moment. There's no time left.
No time left indeed, as back at the council estate, Mustafa/Michael gets a text that the bomb will be delivered to the flat soon, following which they will get more instructions. After planting the bomb in Central London, they are told they have 90 minutes to get clear of the blast. But suddenly, Leigh arrives at the door with a heater, have mentioned earlier how cold Mustafa/Michael's room was. Furious that he would allow an outsider to enter their domain, Samir flips out and stabs Leigh on the stomach, prompting Mustafa/Michael to grab him by the head and slam it repeatedly against the table until he's unconscious. Running to Leigh's aid, Zaf finds that she is dead. Distraught, Mustafa/Michael must still follow Zaf's orders and continue with the plan. Only then would he be able to help Mi-5 stop the bomb and catch the culprits. Adam and a team come in to clean up the mess and plant a bag of heroin, so when Hanif comes by with the van, Zaf convinces Hanif that Samir was an untrustworthy junkie.
Now in possession of the van and the bom, Mustafa/Michael and Zaf drive into London. They will follow instructions then pretend to be devastated when the bomb doesn't go off. Back at headquarters, Ruth has picked up a call from Hanif's superior. As it turns out, it is a suicide mission, but Mustafa/Michael and Zaf don't know that. Instead of allowing them to escape after planting the bomb, there is somebody on the ground who will detonate the bomb when it arrives. With Adam chasing down the van and Mi-5 trying to track down the location of the man with the detonating device, the clock is ticking. HQ finds an infrared signal on their radar, and the tracking device they already have on the van is getting closer and closer within range of said signal. Special Branch has armed police on route with orders to stop the van, but that would include shooting Zaf in the process. Telling them to hold off, Adam manages to jump in front of the van and stop it before it reaches the signal. Convincing Mustafa/Michael to flee to a nearby mosque and talk to the Imam for protection, he sends the former terrorist on his way. But now the detonation man is on the move, getting closer and closer to the target.
But...Adam cannot confirm the identity of the detonation man and neither can Special Branch, and considering the risk of the armed police opening fire on an innocent civilian, he begs them to hold fire. But with Ruth on comm explaining to him the magnitude of what would happen if this man got within range of the van, Adam gives the order to shoot. One man is taken down, and a worried Adam runs up and checks the body, finding a detonation device in his hands. Crisis averted.
Cleaning up the mess of the operation, Michael has agreed to reveal the addresses of all the Al Qaeda safe houses. As for Zaf's undercover terrorist? He has "killed himself" instead of being taken by police. Although they are forced to release Kallis back into the world, they know that they will always have the upper hand on him.
As Mi-5 grabs all evidence back at the council estate, Zaf finds a snow globe of Gran Canaria in Michael's room, a souvenir of the vacation Michael and Leigh once spent.
Hey! I Know That Actor!
Larry Lamb, who plays the sadistic arms dealer Iain Kallis, is best known to British television viewers as Mick on "Gavin & Stacey," Archie on "EastEnders," Terry Dunning on "Annie's Bar," Matt Taylor on "Triangle," and Joey Fox on "Fox."
Adhir Kalyan, who played terrorist Samir, is a South African actor known to American audiences as Raja, the star of the sitcom "Aliens in America," Timmy on CBS's "Rules of Engagement," and Dr. Raj Paresh on Ryan Murphy's "Nip/Tuck," as well as roles in the films "Up in the Air," "No Strings Attached," "Fired Up!," and "Paul Blart: Mall Cop."