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Previously on Mi-5
Hoping to keep Iran's nuclear capabilities a secret, Mi-5 puts together a BBC broadcast to fast-track a fake peace deal with the controversial country. But three studio audience members with guns want the truth exposed by any means necessary. For more, read the full episode recap here.
This Week's Episode: "Infiltration"
While Adam (Rupert Penry-Jones) and Ros (Hermione Norris) spend the night rekindling their romance, across town CIA liaison Bob Hogan (Matthew Marsh) strangles media mogul Eric Glogauer to death with a plastic bag.
As Adam is called into the office, Ros gets a call from Magritte (Claire Cox), her Yalta handler, demanding that they meet now lest Ros want her cover blown. At the rendezvous, Magritte informs Ros that American secret services are aware of Yalta's presence, leading to the murder of six Yalta agents within the last 36 hours.
Adam arrives at the office, and the news is bad. Having learned about Yalta, the United States is no longer willing to play nice with Iran. Citing "deliberately provocative comments from the Iranian government," the U.S. is planning on striking their nuclear facilities within 24 hours, which would in turn start another war in the Middle East. The best that Mi-5 can do is limit any violence from occurring within the United Kingdom, and their best bet is establishing a direct line with Yalta, the now-not-so-secret organization dedicated to limiting American power. Since their last good bit of Yalta information--a surveillance picture of Magritte--came from investigative journalist Ben Kaplan (Alex Lanipekun), Jo (Miranda Raison) attempts but fails to make contact with him.
Ros, meanwhile, meets with Magritte at a council estate. As it turns out, Yalta, the secret organization dedicated to limiting American power, has put together an operation--Floodland--which would bring down America's entire military machine, and Glogauer knows something about the activation code. However, Glogauer was not in possession of it, so Magritte is counting on Ros to obtain the code before it's too late.
Without warning, the elevator door at the end of the hallway opens and Hogan emerges, aiming his gun directly at Magritte. But somebody else has been watching and recording this meeting, and out from the shadows emerges Kaplan, hitting Hogan with his bike and allowing Magritte to take out her extendable baton and knock Hogan unconscious. Kaplan runs from the scene, but Magritte knows that there can be no witnesses, and she hands Ros a case containing a poisonous syringe and sends her on her way. After a quick game of cat-and-mouse, Ros spots Kaplan meeting with Jo, handing over the footage he just should. It's all over for Ros. She's busted.
At headquarters, the team discusses what to do with Ros and where to find her when, lo and behold, Ros confidently walks through the glass doors of Section D, knowing that in order to stop this war from happening, she needs to accept her fate. Adam and Harry (Peter Firth) take her to the conference room and accuse her of betraying everybody who's ever trusted her. Defending herself, she says that she's been the one playing Yalta, and that Mi-5 would be lost without the information that the secret organization has provided to her. And besides, isn't sparing Kaplan's life proof enough that she's on their side? Not one to mince words, Harry shouts directly in her face.
"Shut up!" he yells. "Now, you tell me everything. If you don't, do I need to itemize the consequences?"
Opening up, she tells them everything she knows about Floodland, that had she never infiltrated the organization, they wouldn't even know what they were up against. The solution, she says, is to send her in to do her job and obtain the Floodland activation code. After placing her in a holding cell, Harry takes Adam aside and says that they need to send her in empty-handed on a bluff while they find the code on their own, after which they give it to Ros and ensure that she is always in direct contact with headquarters.
Just to hedge his bets, though, Adam stops by Malcolm's (Hugh Simon) desk and asks for TTX2 (Synthetic Tetrototoxin), specifically measured to dose somebody of Ros' bodyweight.
As the plan goes underway, Kaplan sticks around the office and chats with Connie (Gemma Jones) about Glogauer's business practices, how "he mostly let the editors run the paper as they see fit." This leads to talk of Liam Fairfax, once a powerful hacker who went onto invent the Glogauer-owned Siliconation. "Four million players worldwide made him a very rich boy, but not, apparently, a happy one. Two weeks ago he took his own life." A thought occurs: Did powerful hacker Fairfax's stumble upon something and then sell it to Glogauer? If so, where's the damn code?
At a countryside road, Ros swallows a peppermint--actually a tracking device good for around one hour--and is picked up by a mysterious car. Adam and Harry, a couple miles behind, are tracking her from another car, and their hopes that she will lead them to a Yalta hideout comes to fruition. Alas, the mansion in question has high-tech equipment scanning for surveillance, and so knowing that their listening devices are now worthless, they create a diversion--basically, turn on the sprinklers--and Adam makes it onto the property.
Meanwhile at headquarters, the team goes over Fairfax's personal items when Jo notices something: Fairfax's poster of the periodic table has been rearranged. The code must be on the poster. Malcolm breaks the code just in time to send it to Ros via an e-mail "saved draft"--since the e-mail never goes out, it can't be traced.
At the mansion, the code is received, and who should walk in but National Security Coordinator Juliet Shaw (Anna Chancellor), standing upright with no sign of the supposed paralysis that befell her at the end of Series 4. She has been active with Yalta this whole time, working both sides, and now she's demanding proof as to how Ros can be trusted. "Harry followed me here," Ros retorts, "and so did Adam." As Adam listens in from around the corner, Ros continues, telling them that she placed a tracker on Harry. As Juliet, Magritte, Sholto (James Laurenson), and the Yalta goons leave the room to find Harry, Adam sneaks up from behind Ros and holds a syringe to her neck.
Adam: "You should have let me drown when you had the chance."
Ros: "We have to work together."
Adam: "I can't believe I trusted you."
Ros: "It's time to decide, Adam. It's time to make up your mind about what's going on between us."
As Harry is quickly found and brought to another room in the mansion, Adam reluctantly releases Ros, allowing her to proceed with the plan. Meeting with Magritte in the mansion's CCTV surveillance room, Ros knocks her out and allows Adam in. Taking a hard drive, Adam enters the code and downloads Floodland, only to be met with an animated of a bomb counting down. It's a "logic bomb," which proceeds to take all of America's satellites offline, leaving them blind and deaf, unable to attack anybody. On comm, Malcolm tells them that the only way to stop the logic bomb from spreading is for him to get his hands on the actual computer at the mansion. So that means while Malcolm has to get in a car and race to the mansion--with Special Forces also on their way to deal with Yalta--Adam must find a way out with the computer in tow.
Hoping to save Harry, Adam busts into the room where he's being held and takes out the goon on patrol, but cannot seem to get Harry uncuffed. Ever one to put his country before his own life, Harry orders Adam and Ros to leave him behind and escape while they still have the chance. Adam and Ros make it to the edge of the property and hide within the tall weeds. Unsure about their future but knowing the importance of the case, Adam gives her a final kiss and runs for the country road nearby--where he is able to make the computer exchange with Malcolm--allowing Ros to make her way back into the mansion to rescue Harry.
Ros enters the room, knife in hand, and sees a now gagged Harry struggle to say something to her. But it's too late, and the Yalta officials, including Juliet, overtake Ros and bound her to a chair. It seems the lives of these Mi-5 spies are forfeit.
"The world's about to change, Harry," Ros says from her chair. "It's time to pick sides. I know you have no love for the American imperium."
"I have no love for self-appointed saviors, either," he responds, which gets a rise out of Juliet. Saying she was and still is putting Britain first, she reveals a syringe and approaches Ros. "Ros!" Harry says emphatically. "Look at me! You are an outstanding officer. You are my outstanding officer. Don't be afraid."
"Now is not the time to start patronizing me," Ros says. "Don't you know any good jokes?" And with that, Juliet injects her and depresses the plunger, causing Ros to convulse and then go limp. Special Forces enters the mansion and arrests the Yalta operatives, but can do nothing to save Ros.
In the aftermath of the mission, only 6% of America's satellites went out before Malcolm could shut off the logic bomb, and while they cannot currently send out any Iran-targeted missiles, everything will be back up and running within weeks. Hogan goes to Harry and is sorry for his loss, but he still needs verification that the security leak (i.e. Ros) has been plugged.
As Ros' wake concludes, the Mi-5 team exits the church but Adam stays behind, and he can do nothing but watch as Hogan enters, opens the casket, and feels for Ros' pulse.
"I don't care what she did," Adam says, "but you could at least allow her some dignity. Say it. She's dead. Whatever you say about her now, it means nothing." As Hogan leaves, Adam goes over to the open casket and whispers Ros' name. Ros suddenly springs to life, confused and terrified.
"You have to be quiet," Adam says, consoling her. "I switched syringes. You were infected with a synthetic nerve agent. It slows respiration, heart rate, brain activity. Simulates death. I knew the chances were they'd want you dead. I knew how they preferred to do their killing. So I thought I'd save you by getting there first."
"It's fatal 20% of the time," she says, aghast.
"25," Adam responds. "I did kill you, Ros. You're dead. The Americans won't hear any excuses, so you're dead. Inside this bag, there's a change of clothes, a passport, and some money. You walk away and you don't look back. Not ever." She takes his hand. "If I came with you, they'd know. If they know, they'll come after you. I can't let that happen." He helps her out of the casket. "There's never any time, is there? There's never enough time."
"Not for us."
"Not for us."
She touches his cheek. "Don't go missing my funeral."
Ros quietly makes her way out of the church, but catches Jo's eye. But knowing the price they must pay for being spies, Jo remains silent. For now.