Slow Horses has proven to be one of the most compelling thrillers to come from Apple TV+ with a stunning cast of talented actors driving the spy drama forward. Slow Horses first began streaming on the platform in 2022, establishing the world of British espionage as complex and messy with plenty of in-fighting in even the most elite agencies.

Of course, the antics of these spies are highly fictionalized, but the incredible cast is able to take these misadventures and turn them into something profound and gritty. And with the legendary Oscar-winning Gary Oldman leading the series, the foundation is firm.

However, the series also relies on a healthy mix of fresher talent and more experienced actors to round out the show. The results speak for themselves, as these incredible actors deliver strong performances and chemistry throughout.

Gary Oldman as Jackson Lamb

• Date of Birth: March 31, 1958
• Active Since: 1982

Actor: Gary Oldman was born in London, England. He began his career in theaters, where he worked alongside the Royal Shakespeare Company. He then rose to prominence for his breakout role as Sid Vicious in Sid and Nancy. Oldman is now a household name, having won an Oscar for his performance in Darkest Hour, and appearing in several major franchises.

Previously In: Sid Vicious in Sid and Nancy (1986), Dracula in Bram Stoker’s Dracula (1992), Zorg in The Fifth Element (1997), Sirius Black in the Harry Potter franchise, Jim Gordon in The Dark Knight franchise, George Smiley in Tinker Tailor Soldier Spy (2011), and Harry Truman in Oppenheimer (2023)

Character: Jackson Lamb is in charge of Slough House, which is often referred to as the home of the “Slow Horses.” In other words, Lamb is in charge of the less desirable members of MI5. Despite Lamb’s gruff appearance and his harsh words, he is fiercely protective of his agents, and a legend in the Service.

Jack Lowden As River Cartwright

• Date of Birth: June 2, 1990
• Active Since: 2010

Actor: Jack Lowden was born in Essex, England. Like Oldman, Lowden got his start in acting onstage, before transitioning to screen acting. His big break came when he landed a leading role in the BBC Miniseries, War and Peace, an adaptation of the classic novel. Lowden has won two BAFTA Awards.

Previously In: Nikolai Rostov in War & Peace (2016), Collins in Dunkirk (2017), Henry Darnley in Mary Queen of Scots (2018), and Sauron in The Lord of the Rings: Rings of Power (2024)

Character: River Cartwright was a promising new recruit for MI5, having a notable pedigree as his grandfather, David Cartwright was a high-ranking agent before retiring. However, despite his skill and ambition, River often finds himself caught up in chaos and tragedies that have led to him being exiled to Slough House.

Rosalind Eleazar As Louisa Guy

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• Date of Birth: August 29, 1988
• Active Since: 2015

Actor: Rosalind Eleazar was born in London, England. Eleazar is relatively new to acting compared to many of her co-stars in Slow Horses. However, despite only breaking into credited screen acting since 2015, Rosalind has quickly established herself as a talented performer. Outside of playing Louisa Guy, her most notable role was in the 2019 feature film, The Personal History of David Copperfield.

Previously In: Agnes Wickfield in The Personal History of David Copperfield (2019), and Yelena in Uncle Vanya (2020)

Character: Louisa Guy is a skilled MI5 agent, but like her colleagues in Slough House, mistakes in her career led to her less favorable assignment. Guy has formed a close connection to River over their years working together, but she has also suffered greatly from her time in the Service.

Christopher Chung as Roddy Ho

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• Date of Birth: July 13, 1988
• Active Since: 2011

Actor: Christopher Chung was born in Australia before relocating to London in 2012. Chung was born to an Irish mother and a Malaysian Chinese father, and the pair originally met in London. Chung’s first major role came when he was cast in Waterloo Road, a British drama series.

Previously In: Archie Wong in Waterloo Road (2013-2014)

Character: Roddy Ho is a genius when it comes to computers. However, he appears to have little to no social skills. Ho may be a part of the team at Slough House, but he does his best to exclude himself and push his colleagues away, while also stroking his own ego.

Saskia Reeves As Catherine Standish

• Date of Birth: August 16, 1961
• Active Since: 1984

Actor: Saskia Reeves was born in London, England. Inspired by her father’s work as an actor, singer, and writer, Saskia found herself drawn to performing. Reeves was able to find steady work in stage productions, before landing notable roles in film and TV. Her breakout role came in 1991 when she appeared in Close My Eyes.

Previously In: Natalie in Close My Eyes (1991), Lynda in I.D. (1995), Lady Jessica Atreides in Dune (2000), and Rose Teller in Luther (2010)

Character: Catherine Standish is a loyal employee of MI5, having previously worked under the head of the organization, Charles Partner. However, when Partner died, Standish found herself attached to the more abrasive and harsh Jackson Lamb. While she is not a field agent, her experience makes her an invaluable asset to the team at Slough House.

Kristin Scott Thomas As Diana Taverner

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• Date of Birth: May 24, 1960
• Active Since: 1984

Actor: Kristin Scott Thomas was born in Cornwall, England. Thomas has a long and illustrious career in British film and TV, but her breakout came in 1994 when she also won a BAFTA for her role in Four Weddings and a Funeral. Thomas has continued to gain recognition for her work, with several notable wins, and even an Oscar nomination.

Previously In: Fiona as Four Weddings and a Funeral (1994), Sarah Davies in Mission: Impossible (1996), Katharine Clifton in The English Patient (1996), Sylvia McCordle in Gosford Park (2001), and Crystal in Only God Forgives (2013)

Character: Diana Taverner is the Deputy Director-General of MI5, also referred to as the Second Desk. Though she is technically not in charge, Taverner frequently takes liberties with her role, and has made Slough House into her personal dumping ground for agents that upset or otherwise wrong her. Taverner also has strong ambitions to take the top spot.

Aimee-Ffion Edwards As Shirley Dander

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• Date of Birth: November 21, 1987
• Active Since: 2007

Actor: Aimee-Ffion Edwards was born in Newport, Wales. Her breakout role came early in her career when she landed the role of Sketch in the hit British show, Skins. Edwards has since gone on to play several notable roles despite her comparatively short time as an actor.

Previously In: Sketch in Skins (2008), Jenny Jones in Luther (2011), and Esme Shelby in Peaky Blinders (2013-2022)

Character: Shirley Dander is a more recent addition to the Slough House team, having joined the show in season 2. Dander has had struggles with drug abuse, which led to her assignment, and remains an outsider among the team. However, Dander does have incredible skills of observation.

Slow Horses Supporting Cast & Characters

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Tom Brooke as JK Coe: Tom Brooke is best known for his roles in The Boat that Rocked, Sherlock, and Preacher. As JK Coe, Brooke plays the most recent addition to the team in Slow Horses, having joined in season 4.

James Callis as Claude Whelan: James Callis is best known for appearing in the Bridget Jones series of films, as well as notable appearances in shows like Eureka and 12 Monkeys. Claude Whelan also joined the cast of Slow Horses in season 4 as the new Head of MI5, replacing Ingrid Tearney.

Nick Mohammed as Zafar Jaffrey: Nick Mohammed is a well-known British comedian and actor who rose to prominence for playing a character called Mr. Swallow. However, his role in the hit Apple TV+ series Ted Lasso launched his acting career. Zafar Jaffrey joins Slow Horses season 5 as the Mayor of London.

Ruth Bradley as Emma Flyte: Ruth Bradley has played prominent roles in several projects, including Primeval, Humans, The Innocence Project, and Love/Hate. Emma Flyte is the Head of Security at MI5, and the leader of the Dogs.

Jonathan Pryce as David Cartwright: Jonathan Pryce is a well-known British actor who has won numerous awards, and appeared in notable projects like Terry Gilliam’s Brazil, Evita, Tomorrow Never Dies, Pirates of the Caribbean, and The Crown. As David Cartwright, Pryce plays the legendary grandfather of River Cartwright.