‘Slow Horses’ Season 6 Episode 5 Recap and Ending Explained: River Takes the Fall for Sid

Spy stories love a trade that sounds reasonable on paper and monstrous in practice. In ‘Slow Horses‘, that kind of bargain has become Diana Taverner’s specialty, and this week’s penultimate installment shows exactly what it costs. The episode, titled ‘Sayonara’, arrived on Apple TV on Wednesday, October 14.

The hour picks up right after Sid Baker’s kidnapping, and it tightens the squeeze on nearly everyone in the story. By the end, Sid is on the run, River has made a heroic choice, and Lamb knows far more than Diana would like. Spoilers follow for the full episode and its ending.

The episode opens with Sid, played by Olivia Cooke, trying to escape the Russian agents Jim and Jane after they kidnapped her. In the back of their car, she uses a novelty license plate fridge magnet from the service station gift shop to attack Jane, which sends the car into a crash that seems to kill the assassin outright. Sid drags herself away from the wreck and staggers into the woods, but Jim is close behind.

Luckily, so is River, played by Jack Lowden, who had been following in a borrowed vehicle. Jim drags Sid to a lake and tries to drown her, River intervenes, and Sid hits Jim with a rock. Together they drown him in the lake, and for a moment it looks as though the worst is over.

It is not. MI5 agents arrive to collect the pair, but they are still acting on Diana’s orders, and instead of the Park they take River and Sid to a private airfield and military hangar. No one notices that Jane’s body has disappeared from the crashed car, which suggests the assassin survived.

River convinces the agents to let him make a phone call, and Sid gets Diana on the line. Diana, played by Kristin Scott Thomas, explains that she could not spare the agent used in the hit in Kazan, but she can spare Sid. Sid is to be traded to Vassily, head of the GRU, as a consolation prize.

The episode finally spells out what Diana did. She wanted revenge on Russian agents for an earlier attack, but the agency could not fund the mission, so she ran an off-the-books operation using money from an outside investor. Because the mission was unofficial, her agent needed a cover, and she used Sid’s identity.

Afterward, she wiped every record of Sid from the Park’s archives, which drew attention to Slough House, Sid’s last known department. Vassily then sent Jim and Jane on an assassination spree, with the department’s stolen files as a hit list. Meanwhile, Damien Cantor, the real source of the initial investment, stepped out of the shadows to use the situation to his advantage, and Diana is now vulnerable to blackmail.

First trailer for ‘SLOW HORSES’ Season 6. Releasing September 16 on Apple TV. https://t.co/lktVB8KP8v

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Lamb, played by Gary Oldman, learns about Kazan from River and goes straight to Diana. He has deduced the chain of events leading from Cantor’s initial investment to his hiring of Frank Harkness to tie up loose ends. Diana insists everything is under control, which is the same answer she gives the oversight committee.

That committee has already uncovered her mission and the breach of protocol, partly because of a media interview she gave. Diana addresses the Limitations Committee like a queen, but alone with Lamb, her position is far weaker. The fact that all of Slough House is currently hiding in her holiday home does not help.

The flight to Sofia, Bulgaria, is the real danger. Bulgaria is neutral territory, which means the Russians can do whatever they like with Sid, and Diana still approves the handover. River will not let it happen, so he fights back, and the two steal a car and go on the run from MI5.

After a flirty goodbye, River realizes the only way to give Sid a chance is to buy her time. He tells her to run, and they share a hasty kiss. The episode ends with River driving back toward the agents and allowing himself to be captured.

Elsewhere, the rest of Slough House remains in hiding, with Shirley making Molotov cocktails just in case. Lamb asks Roddy Ho to dig into Cantor’s itinerary, which reveals the media tycoon’s regular visits to a children’s ballet class. There, Lamb spots Natasha, the Russian broker facilitating what is described as the biggest media distribution deal in Russian history.

Cantor has just been invited to a dinner full of the people he wants to do business with, which sets up the finale. Harkness is also still hunting Reece. With only one episode left, River captured, Sid on the loose and Diana’s deal exposed, the season has plenty to resolve.

The season finale arrives on October 21 on Apple TV. Questions remain about where Sid will end up, what punishment awaits River and whether Lamb can turn the situation around before more people die. Diana’s downfall looks possible, but she has survived worse.

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