Created and adapted for television by British screenwriter Will Smith.
Slow Horses first season debuted on April 1, 2022.
Distributed exclusively by Apple TV+.
Slow Horses TV Series Review
Slow Horses is a sharp spy thriller that combines suspense, action, dark humor and memorable characters.
The series follows disgraced MI5 agents working at Slough House under Jackson Lamb.
Season 1 introduces the team as they become involved in a dangerous conspiracy.
Season 2 raises the stakes with a deadly Russian threat and deeper secrets.
Season 3 delivers betrayal, danger and an attack connected to MI5.
Season 4 brings personal revelations and another major security threat.
Season 5 explores political tensions and a dangerous conspiracy.
Season 6 continues with fresh threats, action and shifting loyalties.
CR Rating: 9.2/10.
Slow Horses Actors
Gary Oldman as Jackson Lamb
DOB: March 21, 1958.
Bio: English actor and filmmaker known for his versatility and transformative performances.
He began his career in theatre before moving into film and television, building a reputation for playing complex and distinctive characters.
Role: As Jackson Lamb, Oldman plays the abrasive and disheveled head of Slough House, the MI5 department where agents who have failed or fallen out of favor are sent.
Lamb often appears careless, rude and uninterested in appearances, but beneath his rough exterior is an exceptionally capable intelligence officer.
Seasons & Episodes: S1-6 (36 eps).
Interesting Facts: Oldman has explained that Lamb’s smoking, drinking, unhealthy eating and crude behavior are partly tools of his spycraft, helping people underestimate him.
Notable Works: Tinker Tailor Soldier Spy, Darkest Hour, Harry Potter series, Sid and Nancy.
Jack Lowden as River Cartwright
DOB: June 2, 1990.
Bio: Scottish actor known for his work across television, film and theatre.
He trained at the Royal Scottish Academy of Music and Drama and established himself on stage before gaining wider recognition on screen.
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: S1-6 (36 eps).
Interesting Facts: Lowden’s performance as River has made him one of the central members of the Slow Horses ensemble.
He has also worked with Slow Horses executive producer Adam Randall on other projects.
Notable Works: War & Peace, Dunkirk, Calibre, Mary Queen of Scots, The Long Song, Fighting with My Family.
Kristin Scott Thomas as Diana Taverner
DOB: May 24, 1960.
Bio: British actress whose career spans film, television, and theatre.
She gained international recognition through films such as Four Weddings and a Funeral and The English Patient.
Her performance in The English Patient earned her an Academy Award nomination for Best Actress.
Role: Diana Taverner is a senior MI5 intelligence official and one of the key figures within the agency’s hierarchy.
Strategic, politically aware, and highly ambitious, she frequently clashes with Jackson Lamb and the unconventional agents of Slough House.
Seasons & Episodes: S1-6 (36 eps).
Interesting Facts: Kristin Scott Thomas was born in Redruth, Cornwall, England, and was raised partly in France.
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 from Oldham, Greater Manchester, who began acting at a young age and gained wider recognition for her role as Emma Decody in the television series Bates Motel.
She went on to build a varied film and television career, appearing in Me and Earl and the Dying Girl, Thoroughbreds, Ready Player One, and Sound of Metal.
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&6 (7 eps).
Interesting Facts: Olivia Cooke began acting through the Oldham Theatre Workshop before moving into professional screen work.
Notable Works: Bates Motel, Sound of Metal, House of the Dragon.
Saskia Reeves as Catherine Standish
DOB: August 16, 1961.
Bio: English actress known for her work across film, television, theatre, and radio.
She trained at the Bristol Old Vic Theatre School and has built a career that includes both British television and international productions.
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: S1-6 (35 eps).
Interesting Facts: Saskia Reeves has appeared in productions for the Royal Shakespeare Company and National Theatre and has also worked as a narrator for audiobooks.
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: S1-6 (28 eps).
Interesting Facts: In 2020, Rosalind Eleazar won the Equity Clarence Derwent Award for her performance as Yelena in the West End production of Uncle Vanya.
Notable Works: Missing You, Deep Water, Uncle Vanya.
Christopher Chung as Roddy Ho
DOB: July 13, 1988.
Bio: 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: S1-6 (35eps).
Interesting Facts: Christopher Chung worked as a personal trainer while pursuing his acting career and continues to train clients in London.
Notable Works: Waterloo Road, Doctor Who, Doctors.
Jonathan Pryce as David Cartwright
DOB: June 1, 1947.
Bio: Welsh actor known for his extensive work across theatre, film, and television.
A graduate of the Royal Academy of Dramatic Art, he established himself as a major stage performer before gaining international recognition for films including Brazil, Evita, and The Pirates of the Caribbean series.
Role: David Cartwright is River Cartwright’s grandfather and a retired senior MI5 officer with a legendary reputation within British intelligence.
He has extensive knowledge of the agency and its history and remains connected to its operations through his family and former colleagues.
Seasons & Episodes: S1-6 (15 eps).
Interesting Facts: Jonathan Pryce has won two Tony Awards for his stage work, including one for his Broadway debut in Comedians and another for playing The Engineer in Miss Saigon.
Notable Works: Brazil, The Two Popes, Game of Thrones.
Hugo Weaving as Frank Harkness
DOB: April 4, 1960.
Bio: Australian actor known for his extensive work in film, television, and theatre.
Born in Ibadan, Nigeria, to English parents, he spent parts of his childhood in England, Australia, and South Africa before settling in Australia.
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&6 (10 eps).
Interesting Facts: Hugo Weaving graduated from NIDA in 1981 and made his television debut in the Australian series Bodyline in 1984.
Notable Works: The Matrix, Lord of the Rings, V for Vendetta.
Aimee‑Ffion Edwards as Shirley Dander
DOB: November 21, 1987.
Bio: Welsh actress known for her work in television, film, theatre, and video games.
She gained early recognition as Sketch in the television series Skins before appearing in productions including Luther, Peaky Blinders, Detectorists, and The Crown.
Role: Shirley Dander is an MI5 agent who is transferred to Slough House after an incident that results in her being disciplined.
She becomes part of the Slow Horses team alongside Marcus Longridge and the other agents.
Seasons & Episodes: S2-6 (30 eps).
Interesting Facts: Aimee-Ffion Edwards was born in Newport, Wales, and trained at the Royal Welsh College of Music & Drama.
Notable Works: Luther, Peaky Blinders, Elden Ring.
Sope Dirisu as Sean Donovan
DOB: January 9, 1991.
Bio: British-Nigerian actor known for his work across television, film, and theatre.
He studied economics at the University of Manchester before pursuing acting and trained with the National Youth Theatre.
Role: Sean Donovan is an MI5 agent who is sent to Slough House during the events of Season 3.
He becomes involved in the investigation surrounding a secret MI5 operation and the disappearance of his wife, Alison.
Seasons & Episodes: S3 (6 eps).
Interesting Facts: Sope Dirisu was born in London to Nigerian parents and initially studied economics at the University of Manchester.
Before becoming a professional actor, he was a member of the National Youth Theatre.
Notable Works: Gangs of London, Black Mirror, His House.
Katherine Waterston as Alison Dunn
DOB: March 3, 1980.
Bio: American actress known for her work in film and television.
She studied at the Tisch School of the Arts at New York University and began her career with appearances in independent films before gaining wider recognition.
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).
Interesting Facts: Katherine Waterston is the daughter of actor Sam Waterston and model Lynn Louisa Woodruff.
Notable Works: Inherent Vice, Fantastic Beasts, Alien: Covenant, The World to Come.
More Actors
• Chris Reilly as Nick Duffy.
• Samuel West as Peter Judd.
• Kadiff Kirwan as Marcus Longridge.
• Tom Brooke as J.K. Coe.
FAQ – Slow Horses TV Series
What is Slow Horses about?
Slow Horses follows a group of MI5 agents who have been assigned to Slough House after career mistakes. The team is led by Jackson Lamb, played by Gary Oldman.
Is Slow Horses based on a book?
Yes. The series is based on Mick Herron’s Slough House novels. Season 6 draws from Joe Country and Slough House.
Will there be a Slow Horses Season 7?
Yes. Season 7 has already been announced by Apple TV and will continue the story beyond Season 6.
How many seasons of Slow Horses are there?
Slow Horses currently has six seasons. Season 6 premiered on September 16, 2026, with episodes released weekly.
Where can I watch Slow Horses?
Slow Horses is available to stream on Apple TV, with the first five seasons already available and Season 6 releasing weekly.
Conclusion
Slow Horses is an engaging spy thriller that balances tense missions with dark humor and strong character development.
Across six seasons, it continues to deliver suspense, action and memorable performances.