Apple TV+’s acclaimed spy thriller Slow Horses continues to unravel its intricate web of conspiracies in its sixth season, bringing long-buried secrets and presumed casualties back into the light. Season six, episode five, titled “Sayonara,” delivers a major narrative turning point by officially detailing the fate of Sid Baker, played by Olivia Cooke, and placing her squarely at the center of an explosive international conflict involving MI5 and Russian intelligence.
For years, fans believed Sid Baker had perished following a severe gunshot wound to the head during the first season. However, the series later complicated that narrative, revealing that she actually survived the harrowing ordeal. Speaking to Australian media outlet smh.com.au, actress Olivia Cooke shed light on why her character vanished from the public eye for so long. According to Cooke, Sid was kept hidden away after recovering from her injuries and was only brought back into the main storyline when the plot required her dramatic return.
“I was devastated because I really got invested with River and Sid, but I knew that I was always going to get shot in the head and disappear. Which is a funny thing to know,” Cooke shared regarding her initial exit and eventual comeback.
The Truth Behind Sid Baker’s Survival and Disappearance
In the world of Slow Horses, Sid’s survival came with heavy strings attached. After recovering in a secure hospital setting, Diana Taverner arranged for her to be moved to an isolated English village, keeping her completely out of sight for three years. This elaborate cover-up allowed MI5 to bury an embarrassing and dangerous operational mess, as Moody-an operative doing Taverner’s dirty work-was the one who originally shot Sid.
By season six, Sid’s reappearance shatters the guilt that fellow agent River Cartwright (Jack Lowden) has carried for years. Believing he was partly responsible for her death, River’s relief quickly turns into high-stakes panic when shadowy assassins Jim and Jane track them down. The ensuing escape brings to light an even darker conspiracy involving a sus**cious travel order to Kazan, Russia. River and Sid uncover a theory that someone within MI5 used Sid’s identity to carry out a covert assassination, effectively painting a target on her back for Russian operatives seeking revenge.
Confronting MI5 and Regent’s Park
As episode five progresses, the narrative intensifies after MI5 captures Sid and River, forcing them to navigate the dangerous political maneuvering of Regent’s Park. Despite warnings from her peers, Sid maintains a dangerous level of trust in Diana Taverner, attempting to use payphones to reach out to the Deputy Director. Whether that trust is a brilliant tactical move or a fatal miscalculation remains a central tension of the season.
Meanwhile, Jackson Lamb (Gary Oldman) continues digging into the broader conspiracy, uncovering stolen files, compromised agents, and the true cost of Taverner’s calculated risks. With supporting characters like Moira Tregorian surviving staged gas leaks and Louisa Guy stepping back into the field, the scattered members of Slough House are finally being pulled together by fear and necessity.
As Slow Horses season six rolls toward its dramatic conclusion, Sid Baker’s return completely reframes the power dynamics within MI5, proving that in Jackson Lamb’s world, no secret stays buried forever.
