Created and adapted for television by British screenwriter Will Smith.
Slow Horses first season debuted on April 1, 2022.
Distributed exclusively by Apple TV+.
Series Review
Slow Horses is a clever and funny spy series about a group of MI5 agents who have messed up in the past and been sent to “Slough House”, a place for failures.
But even though they’re seen as useless, they keep getting caught up in real and dangerous missions.
In Season 1, we meet Jackson Lamb and his odd team as they stumble onto a deadly plot.
Season 2 raises the action and danger, while Season 3 dives deeper into each character’s past.
Season 4 adds more twists and tough choices, and by Season 5, the story reaches an exciting and emotional point.
The show mixes serious spy action with sharp humour and human moments. It’s smart, gripping, and full of great performances, especially Gary Oldman’s.
Slow Horses proves that even the “rejects” of MI5 can be the most unpredictable heroes.
Ratings
• IMDb: 8.3/10
• Rotten Tomatoes: 97%
• Google Audience Score: 89% liked this TV show.
Slow Horses Actors
Gary Oldman as Jackson Lamb
DOB: March 21, 1958.
Bio: Gary Oldman is one of the most acclaimed and transformative actors of his generation.
Known for his extraordinary range and meticulous character work, he has portrayed everyone from punk icons to political leaders.
His Oscar-winning turn as Winston Churchill in Darkest Hour cemented his reputation as one of cinema’s great chameleons.
Role: As Jackson Lamb, Oldman plays the slovenly, razor-sharp head of Slough House, MI5’s purgatory for disgraced or failed agents.
Beneath the cynicism and perpetual disarray, Lamb hides a brilliant mind and a deep sense of loyalty to his “slow horses.”
Seasons & Episodes: S1–5 (30 eps).
What to Expect: Cutting witty monologues, unexpected empathy, whiskey-fueled strategies, and even strategic flatulence.
Favorite Things: Cigarettes, old-school rock (Bob Dylan, The Rolling Stones), comfort food, and live theatre.
Notable Works: Tinker Tailor Soldier Spy, Darkest Hour, Harry Potter series, Sid and Nancy.
Jack Lowden as River Cartwright
DOB: June 2, 1990.
Bio: Jack Lowden is a BAFTA-winning Scottish actor celebrated for his emotionally rich and quietly powerful performances across stage and screen.
A graduate of the Royal Scottish Academy of Music and Drama, Lowden rose to prominence with War & Peace and earned widespread acclaim for his turn in Dunkirk.
Role: River Cartwright is an ambitious MI5 agent whose career is derailed after a disastrous training operation lands him in Slough House, the agency’s dumping ground for disgraced spies.
His ongoing struggle between ambition, integrity, and disillusionment drives much of the series’ emotional core.
Seasons & Episodes: S1–5 (30 eps).
What to Expect: A gripping arc, anger, redemption, mentorship tension, and surgical emotional depth .
Favorite Things: Wild swimming in Scotland, listening to audiobooks, and sketching during downtime.
Notable Works: Dunkirk, War & Peace, Dunkirk.
Kristin Scott Thomas as Diana Taverner
DOB: May 24, 1960.
Bio: Dame Kristin Scott Thomas is one of Britain’s most distinguished actors, known for her blend of elegance, intelligence, and emotional precision.
After her breakout in Four Weddings and a Funeral, she achieved international acclaim and an Academy Award nomination for The English Patient.
Role: Diana Taverner is the calculating and fiercely ambitious Deputy Director General of MI5.
A master strategist and survivor within the political labyrinth of British intelligence, she navigates her uneasy alliance and rivalry with Jackson Lamb while pursuing her own agenda.
Seasons & Episodes: S1–5 (30 eps).
What to Expect: Cold, controlled scheming, and verbal duels with Lamb.
Favorite Things: Long countryside walks, reading classic literature, and maintaining a timeless minimalist wardrobe.
Notable Works: The English Patient, Four Weddings and a Funeral, Gosford Park.
Olivia Cooke as Sidonie “Sid” Baker
DOB: December 27, 1993.
Bio: English actress celebrated for her versatility and emotional depth across film and television.
Born in Oldham, Greater Manchester, she trained at the Oldham Theatre Workshop before gaining attention with her breakout role in Bates Motel.
Since then, she has built an impressive résumé spanning indie dramas, blockbusters, and prestige TV.
Role: Sidonie “Sid” Baker is one of the most capable agents at Slough House, a sharp, resourceful intelligence officer whose calm intellect and field acumen often outshine her disgraced colleagues.
Her loyalty and quick thinking make her a linchpin in the early seasons, and her fate has lasting consequences for the team.
Seasons & Episodes: S1 (3eps).
What to Expect: Tech-savvy revelations, biting humor, and emotional grit.
Favorite Things: Ballet, British tea culture, simple home cooking, and reading detective fiction.
Notable Works: Bates Motel, Sound of Metal, House of the Dragon.
Saskia Reeves as Catherine Standish
DOB: August 16, 1961.
Bio: A distinguished British actress celebrated for her nuanced, emotionally grounded performances across film, television, and theatre.
A veteran of the Royal Shakespeare Company and National Theatre, Reeves is known for bringing quiet strength and subtle vulnerability to every role.
Role: Catherine Standish serves as Jackson Lamb’s devoted but long-suffering assistant at Slough House.
A former MI5 operative herself, she balances professionalism with deep compassion, acting as the emotional core of the dysfunctional intelligence team.
Seasons & Episodes: S1–5 (29 eps).
What to Expect: Dry humor, heartfelt restraint, and surprising wisdom.
Favorite Things: Gardening, maintaining order in small rituals, and a perfectly brewed morning coffee.
Notable Works: Close My Eyes, The Outrun, Us.
Rosalind Eleazar as Louisa Guy
DOB: August 29, 1988.
Bio: British actress celebrated for her depth, precision, and magnetic screen presence.
A graduate of the London Academy of Music and Dramatic Art (LAMDA), she has built a reputation through standout performances in both period dramas and contemporary thrillers.
Role: As Louisa Guy, Eleazar plays one of Slough House’s most capable and composed field agents.
Her professionalism and sharp instincts often make her the anchor in a sea of dysfunction, while glimpses of emotional vulnerability reveal the toll of espionage and loss.
Seasons & Episodes: S1–5 (25 eps).
What to Expect: Emotional arcs, sharp instincts, and dark humor.
Favorite Things: Thought-provoking conversation, fine art, and moments of solitude.
Notable Works: Missing You, Deep Water, Uncle Vanya.
Christopher Chung as Roddy Ho
DOB: July 13, 1988.
Bio: Christopher Chung is an Irish–Malaysian–Chinese actor who broke out with his scene-stealing performance as Roddy Ho in Slow Horses, earning a BAFTA nomination.
A former personal trainer turned stage and screen actor, Chung is celebrated for bringing authenticity and subversive charm to his roles.
Role: As Roddy Ho, Chung plays Slough House’s eccentric tech wizard, cocky, socially oblivious, yet crucial to every mission’s success.
Beneath the bravado lies insecurity and a longing for validation, which make him both hilarious and oddly relatable.
Seasons & Episodes: S1–5 (29 eps).
What to Expect: Tech breakthroughs spiced with quirky humor and mentorship moments.
Favorite Things: Fitness training, gaming marathons, ramen nights, and coding challenges.
Notable Works: Waterloo Road, Doctor Who, Doctors.
Jonathan Pryce as David Cartwright
DOB: June 1, 1947.
Bio: Sir Jonathan Pryce is one of Britain’s most acclaimed actors, known for his magnetic presence on both stage and screen.
From his dystopian breakout in Brazil to his Academy Award–nominated performance as Pope Francis in The Two Popes, Pryce has mastered roles that blend intellect, moral ambiguity, and aching humanity.
Role: As David Cartwright, River’s grandfather and a retired MI5 legend, Pryce embodies a man haunted by his past deeds and the fading sharpness of his once-formidable mind.
His presence ties the series’ generational and moral conflicts together.
Seasons & Episodes: S1–5 (14 eps).
What to Expect: Quiet authority, heartbreak, and a stirring family legacy.
Favorite Things: Reading spy memoirs, playing chess, and long countryside walks.
Notable Works: Brazil, The Two Popes, Game of Thrones.
Hugo Weaving as Frank Harkness
DOB: April 4, 1960.
Bio: Hugo Weaving is a powerhouse of international cinema, best known for iconic roles like Agent Smith in The Matrix trilogy, Elrond in The Lord of the Rings, and V in V for Vendetta.
Trained at Sydney’s NIDA, Weaving has balanced blockbuster dominance with critically acclaimed indie and stage work (The Interview, Little Fish, The Resistible Rise of Arturo Ui).
Role: Frank Harkness, River Cartwright’s estranged father, is a seasoned yet ethically conflicted MI5 operative whose past is riddled with manipulation, secrecy, and betrayal.
His return in later seasons exposes the murky intersections between personal loyalty and professional deceit.
Seasons & Episodes: S4 (5 eps).
What to Expect: Tense encounters, chilling charm, and an unpredictable father-son duel.
Favorite Things: Gardening, home pickling, supporting Australian theatre, and avoiding the trappings of celebrity.
Notable Works: The Matrix, Lord of the Rings, V for Vendetta.
Aimee‑Ffion Edwards as Shirley Dander
DOB: November 21, 1987.
Bio: Aimee-Ffion Edwards is a Welsh powerhouse of performance known for her emotionally charged roles across British television.
Her breakout came in Skins, followed by unforgettable turns in Peaky Blinders (as Esme Shelby), Broadchurch, and The Crown.
Role: Shirley Dander is a brilliant but impulsive agent reassigned to Slough House after a classified mission goes disastrously wrong.
Quick-witted and prone to volatility, she adds both spark and unpredictability to the team dynamic.
Seasons & Episodes: S2–5 (24 eps).
What to Expect: Emotional tension, mental strain, and cunning diligence.
Favorite Things: Sketching, long walks through city neighborhoods, and music from her Welsh roots.
Notable Works: Luther, Peaky Blinders, Elden Ring.
Sope Dirisu as Sean Donovan
DOB: January 9, 1991.
Bio: An alum of the Royal Shakespeare Company and a former National Youth Theatre standout, Ṣọpẹ́ Dìrísù is a British-Nigerian actor praised for both classical precision and modern grit.
With acclaimed performances in His House, Gangs of London, and Black Mirror, Dìrísù has carved a niche for portraying men torn between duty and conscience.
Role: Sean Donovan is a disciplined and enigmatic former MI5 agent reassigned to Slough House under opaque circumstances.
His calm professionalism and unspoken history introduce new tension and unpredictability into the team’s ranks.
Seasons & Episodes: S3 (6 eps).
What to Expect: Field intensity, moral ambiguity, and emotional heat.
Favorite Things: Theatre, cooking elaborate meals, and problem-solving through chess and reading.
Notable Works: Gangs of London, Black Mirror, His House.
Katherine Waterston as Alison Dunn
DOB: March 3, 1980.
Bio: A graduate of NYU’s Tisch School of the Arts, Katherine Waterston is known for bringing depth and sensitivity to roles across film and television.
With breakout turns in Inherent Vice, Fantastic Beasts, and Alien: Covenant, she has carved a reputation for emotionally nuanced, introspective performances.
Role: Alison Dunn is River Cartwright’s introspective and distant sister, whose return in Season 3 exposes long-buried family wounds and hidden loyalties.
Her dynamic with River adds a personal undercurrent to the season’s broader spy intrigue.
Seasons & Episodes: S3 (2 eps).
What to Expect: Subtle emotional complexity, familial tension, and moral exploration.
Favorite Things: Literature, meditation, and exploring character psychology in her roles.
Notable Works: Inherent Vice, Fantastic Beasts, Alien: Covenant, The World to Come.
More Actors
Season 1 (2022)
• Dustin Demri‑Burns as Min Harper.
• Steven Waddington as Jed Moody.
• Paul Higgins as Struan Loy.
• Chris Reilly as Nick Duffy.
• Freddie Fox as “Spider” Webb.
• Samuel West as Peter Judd.
• Antonio Aakeel as Hassan Ahmed.
Season 2 (2022)
• Kadiff Kirwan as Marcus Longridge.
• Rade Šerbedžija as Nikolai Katinsky.
• Alec Utgoff as Arkady Pashkin.
• Catherine McCormack as Alex Tropper.
• Adrian Rawlins as Duncan Tropper.
• Tamsin Topolski as Kelly Tropper.
Season 3 (2023)
• Charlie Rowe as Ben Dunn.
• Eliot Salt as Sarah Dunn.
• Nick Blood as Sturges.
• Gavin Spokes as Sly Monteith.
Season 4 (2024)
• Tom Brooke as J.K. Coe.
• Joanna Scanlan as Moira Tregorian.
• Ruth Bradley as Emma Flyte.
• James Callis as Claude Whelan.
Season 5 (2025)
• Fady Elsayed as Kamal.
• Monty Ben as Farouk.
• Hiba Bennami as Tara.
• Nick Mohammed as Mayor Zafar Jaffrey.
FAQ – Slow Horses TV Series
What is Slow Horses about?
Slow Horses follows a group of failed MI5 agents led by Jackson Lamb as they tackle dangerous spy missions while trying to redeem their careers.
How many seasons and episodes are there?
As of late 2025 the series has 5 seasons and 30 episodes.
Has Slow Horses been renewed for more seasons?
Yes. Apple TV+ has officially renewed the show for Season 6 (and Season 7 was also announced); Season 6 will adapt Joe Country and Slough House. More on EW
How many seasons will Slow Horses run?
Apple TV+ has greenlit Seasons 6 and 7 already. Season 6 will adapt Joe Country and Slough House, while Season 7 will follow Bad Actors.
Is each season standalone or sequential?
Each season adapts a different book from Mick Herron’s series.
While standalone plots exist, a continuing character arc and relational development create a cohesive narrative through Season 4.
Where and how can I watch it?
Slow Horses is exclusive to Apple TV+, available in over 100 countries.
How many Emmy’s did slow horses win?
Slow Horses has won one Primetime Emmy Award, Outstanding Writing for a Drama Series in 2024, out of nine nominations.
Conclusion
In the end , Slow Horses proves that spy stories thrive when centered on flawed characters rather than flawless heroes.
Its blend of dark comedy, emotional stakes, and clever plotting keeps viewers invested from the first desk-bound mission to the final clandestine showdown.
With a powerhouse cast led by Gary Oldman and Jack Lowden, every episode delivers unexpected twists and unforgettable moments.
Whether you love sharp dialogue or tense suspense, Slow Horses stands out as a modern classic that redefines what a spy drama can be.