While all six episodes were screened in advance, for embargo reasons, story details will be restricted to Episode 1 “Bad Dates”.

Another day, another bizarre terrorist attack in London for Slough House to deal with, this time on the heels of a divisive mayoral election between current liberal in-office Zafar Jaffrey (Nick Mohammed) and conservative Dennis Gimball (Christopher Villiers). After a mass shooting occurs in the Abottsfield Shopping Center, seemingly targeted a campaigner for Jaffrey, the shooter (Edward Davis) is also mysteriously taken out. His motivations likely political, though his deployment a mystery, and a white Ford Transit van fleeing the scene is the only link MI5’s black sheep team have to stopping further terrorist attacks.

This season, based this time off of Mick Herron’s fifth book in the Slow Horses series London Rules and directed by Saul Metzstein, can’t help but feel relevant to the current era of political hysteria, with the manipulation of the mentally unwell, incel communities, misinformed individuals, and politically-obsessed radicals riled up by online hate groups and loud and proud leaders with extreme rhetorics. This specific terrorist group is able to use these misguided people as weapons, and in some cases, distractions. MI-5, led by Director-General Claude Whelan (James Callis), continue to 20% of the work that Slough House, once again, is able to accomplish despite their obvious deficiencies (still underestimated after all this time!)

Gary Oldman’s brilliant but flatulent curmudgeon Jackson Lamb continues to keep his team on edge, frustrated with his non-compliance and abillity to shrug off every ounce of information they give him. But despite their frustrations, Lamb is always ten steps ahead. As Shirley (Aimee-Ffion Edwards) saves a careless, and deliriously happy Roddy Ho from being run over by the same white van of the crime, and suspects that Roddy may be a target, Lamb’s response is nothing more than a joke. “I’d like to think of Ho getting run over accidentally, it would be robbing the rest of us a moment’s pleasure.” Despite Lamb’s obvious pessism, the rest of her team seems unbothered by her suspicion as well. Even River simply cracks “I believe he was hit by a car as are many that cross roads.” Shirley’s attitude is continuously questioned by her team and often amplified into extremity as she still mourns the death of her fellow agent Marcus in the last season. But none are less concerned about the matter more than Roddy himself. Oh, Roddy. The type of man who would likely find himself at home in the incel community if he wasn’t so arrogant. Christopher Chung continues to play Ho with the perfect amount of smarmy pompousness and self-satisfaction, shocking his team with the discovery that he has the capability of scoring a hot date, the source of his current deliriousness. Though, Roddy and “hot date” belonging in the same sentence must be too-good-to-be-true.

River Cartwright (Jack Lowden), still affected by his traumatic parentage reveal last season, struggles with the continued progression of his grandfather David’s dementia (Jonathan Pryce, back once again playing another memory-impaired senior-citizen, just appearing in The Thursday Murder Club film adaptation) as well as the departure of Louisa Guy (Rosalind Eleazar), who plans to take a six-month retirement from the force. Paired much this season with the amusingly sociopathic J.K. Coe (Tom Brooke), he isn’t allowed much for emotional support conversations. For five seasons now, River has known he is better than MI5 treats him and his dedication is, at this point, generous.

This ensemble, while ever-changing, continues to astound and delight. Oldman is perhaps the best he’s ever been in the role of Jackson Lamb and that’s saying a lot. Initially introduced in Season 1 producing a loud, drunken fart, Lamb is a character you can smell off the screen, and yet his eyes are so filled with stories that would make most of his team’s stomachs churn should they be told. We know by now most of Lamb’s derisive attitude is a cover. Season Two was the furtherest look into his past we’ve gotten so far, explaining the lengths he will go to do his job right, and this current season pushes that notion even further. But the darkness of Lamb still somehow produces some of the funniest line readings in any current television series. The “weaponized, story-based fart”, hilariously publicized by show-runner Will Smith in preparation for this upcoming season, is, let’s just say, properly deployed.

As always, Slow Horses continues to be a magnificent success for Apple, and teases a juicy follow-up season in its closing moments as always, though its main story this time around may not have the same edge-of-your-seat grip and personal stakes as the previous fourth season (which is probably the series’ current peak). Some character arcs aren’t properly given the type of closure, but will they ever find closure? Will they continue to just spin their wheels in the purgatory known as Slough House? Do they have the capacity to move on? Some, like Lamb, may just be who they are forever, whether they like it or not.

The fifth season of “Slow Horses” premieres September 24, 2025 on Apple TV+.