The Slow Horses cast features Gary Oldman, Jack Lowden and Kristin Scott Thomas. This info article contains minor spoilers and character details for Will Smith’s Apple TV+ series. Check out more streaming guides in Vague Visages’ Know the Cast section.

Slow Horses follows a group of MI5 outcasts. When River Cartwright blows an operation, he attempts to repair his reputation under the guidance of spy legend Jackson Lamb. Meanwhile, a high-ranking MI5 officer enlists a female agent named Sidonie Baker to keep an eye on the newest resident of “Slough House.” As River and Jackson investigate a terrorist group, they learn about its connection to a Pakistani military officer. Here’s every main performer and character in Slow Horses, an adaptation of Mick Herron’s 2010 novel.

Read More at VV — Know the Cast: ‘CODA’

Slow Horses Cast: Gary Oldman as Jackson Lamb

Character Profile: The Slough House boss, a veteran MI5 agent. He frequently passes gas in public and has few fucks to give. Jackson investigates the kidnapping of a Muslim student.

Oldman’s Resume: Lee Harvey Oswald in JFK (1991), Dracula in Bram Stoker’s Dracula (1992), Gordon in The Dark Knight (2008), George Smiley in Tinker Tailor Soldier Spy (2011), Winston Churchill in Darkest Hour (2017)

Read More at VV — Know the Cast: ‘The Bubble’

Slow Horses Cast: Jack Lowden as River Cartwright

Character Profile: A disgraced MI5 agent. He gets reassigned to MI5 Aldersgate aka “Slough House” and looks into a man named Hobden. River learns that a female agent was assigned to track his activity.

Lowden’s Resume: Thommo in ’71 (2014), Collins in Dunkirk (2017), Vaughn in Calibre (2018), Zak Knight in Fighting with My Family (2019),  Ian Macdonald in Small Axe “Mangrove” (2020)

Read More at VV — Know the Cast: ‘Pachinko’

Slow Horses Cast: Kristin Scott Thomas as Diana Taverner

Character Profile: MI5’s second-in-command. She’s the director of operations and, more specifically, personnel. Diana investigates a “bad tradecraft” mistake.

Thomas’ Resume: Fiona in Four Weddings and a Funeral (1994), Katharine Clifton in The English Patient (1996), Sylvia McCordle in Gosford Park (2001), Crystal in Only God Forgives (2013), Clemmie in Darkest Hour (2017)

Read More at VV — Know the Cast: ‘All Hail’

Slow Horses Cast: Olivia Cooke as Sidonie Baker

Character Profile: An MI5 agent. She tracks River’s activity while befriending him. Sid nearly gets killed in the second episode.

Cooke’s Resume: Emma Decody in Bates Motel (2013-17), Rachel in Me and Earl and the Dying Girl (2015), Amanda in Thoroughbreds (2017), Art3mis/Samantha in Ready Player One (2018), Lou in Sound of Metal (2019)

Read More at VV — Know the Cast: ‘Severance’

Slow Horses Cast: Jonathan Pryce as David Cartwright

Character Profile: River’s grandfather. He warns him about the dangers associated with Slough House.

Pryce’s Resume: James Lingk in Glengarry Glen Ross (1992), Elliot Carver in Tomorrow Never Dies (1997), High Sparrow in Game of Thrones (2015-16), Joe Castleman in The Wife (2017), Cardinal Jorge Bergoglio/Pope Francis in The Two Popes (2019)

Read More at VV — Know the Cast: ‘Moonshot’

Slow Horses Cast: Antonio Aakeel as Hassan Ahmed

Character Profile: A Muslim hostage from Birmingham. He’s a British-Asian student at Leeds University. Hassan is also the nephew of a Pakistani military intelligence officer.

Aakeel’s Resume: Ben in Granada Nights (2011), Nitin in Tomb Raider (2018), Omar in Eaten by Lions (2018), Rafe Lahiri in Dublin Murders (2019), Paani in Octonauts: Above & Beyond (2021)

Read More at VV — Know the Cast: ‘The Afterparty’

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The Slow Horses cast also includes Sam Hazeldine (Peaky Blinders, The Last Duel), Rosalind Eleazar (Harlots, The Personal History of David Copperfield), Saskia Reeves (Luther, Our Kind of Traitor), Christopher Chung (Waterloo Road, Doctors) and Chris Reilly (Game of Thrones, Wrath of Man).

Q.V. Hough (@QVHough) is Vague Visages’ founding editor.