48 Fun Facts About Slow Horses

Who plays Jackson Lamb in Slow Horses?

Gary Oldman plays Lamb, who secretly slips a gun into Standish's handbag so she can free them both after MI5 seizes them in series 1.

What is Jackson Lamb notorious for doing in front of his agents in Slow Horses?

Farting is Lamb's calling card, and one critic joked his farts deserve their own SAG card, yet he is fiercely protective of his agents.

On which streaming service did Slow Horses premiere?

Apple TV+ renewed Slow Horses for a seventh series in July 2025, before its fifth series had even premiered.

What does Jackson Lamb call the agents he is loyal to in Slow Horses?

Joes is Herron's word for agents, and Lamb, now a shambles, was once a formidable joe himself in Berlin.

Who adapted Slow Horses for television and served as its showrunner?

Will Smith, a Thick of It writer, won a 2024 Emmy for Slow Horses and began his speech: 'First of all, relax. Despite my name, I come in peace.'

Who plays River Cartwright in Slow Horses?

Jack Lowden plays River, who in series 4 lets MI5, and even Louisa, believe he has been shot dead by his own grandfather.

Who plays Diana Taverner in Slow Horses?

Kristin Scott Thomas plays Taverner, who in series 3 quietly feeds a rogue team hunting MI5's buried Footprint file.

What is Diana Taverner's MI5 designation through Slow Horses' first five series?

Second Desk means deputy director general, and Taverner only becomes First Desk when Claude Whelan is pressured into resigning at the end of series 5.

Who plays River's grandfather David Cartwright in Slow Horses?

Jonathan Pryce plays David, whom River commits to a care home against his wishes at the end of series 4.

In Slow Horses, who is revealed to be River Cartwright's biological father?

Frank Harkness, a CIA operative turned mercenary played by Hugo Weaving, raises sons as trained killers and slips a live grenade into River's hood.

Who plays Catherine Standish in Slow Horses?

Saskia Reeves plays Standish, who quits Slough House in series 3 when Lamb reveals her late idol, Charles Partner, had planned to frame her.

Why was Louisa Guy sent to Slough House in Slow Horses?

She lost a tail on a suspect, and after Min Harper's murder Louisa confronts the Russian she blames with a utility knife, meaning to torture him.

What is Roddy Ho's speciality in Slow Horses?

Computers are Roddy Ho's gift, yet in series 4 his online girlfriend, Kim, turns out to be a scam bot.

Who plays Shirley Dander in Slow Horses?

Aimee-Ffion Edwards plays Shirley, who rides to Roddy's rescue when the assassin Chernitsky ambushes him on a train in series 2.

Who plays MI5 Director General Ingrid Tearney in Slow Horses?

Sophie Okonedo plays Tearney, who is forced to resign after River leaks proof that she covered up a botched trial of an MI5 hacking device.

Why was Min Harper assigned to Slough House in Slow Horses?

He left a secret disk on a train, and in series 2 Min is murdered by Russian heavies who stage it as a drunken cycling accident.

Who plays Sidonie "Sid" Baker in Slow Horses?

Olivia Cooke plays Sid, whose MI5 records are wiped after she is shot in series 1, before her surprise return in series 6.

Why was Struan Loy banished to Slough House in Slow Horses?

An inappropriate work email got Struan Loy exiled, and in series 1 Taverner has him quietly detained at MI5 headquarters and pressed for evidence against Lamb.

What is the nickname of MI5's internal affairs and tactical unit in Slow Horses?

The Dogs are the unit Taverner sends to hunt down Lamb and his agents when her kidnapping scheme unravels in series 1.

Who plays the ambitious politician Peter Judd in Slow Horses?

Samuel West plays Judd, who as Home Secretary refuses Ingrid Tearney's resignation letter so he can keep her in place.

Critics have likened Slow Horses' Peter Judd to which real British politician?

Boris Johnson fits Judd, Herron has said, 'but so do many other politicians': he wrote the MP as a generic right-wing bogeyman.

Who plays bumbling MI5 Director General Claude Whelan in Slow Horses?

James Callis plays Whelan, who exiles records keeper Moira Tregorian to Slough House after she unwittingly finds evidence of his visits to prostitutes.

Which far-right group kidnaps student Hassan Ahmed in Slow Horses' first series?

The Sons of Albion kidnapping was engineered by MI5's own Diana Taverner as a false-flag operation, with her mole planted inside the group.

Which insect names the secret Russian programme at the heart of Slow Horses' second series?

Cicada was a sleeper programme MI5 had long written off as a hoax, until ex-spy Dickie Bow typed the word into his phone as he died.

In which village does much of Slow Horses' second series take place?

Upshott is where River befriends a family whose seemingly innocent mother turns out to be the real Russian sleeper agent.

How is ex-MI5 officer Dickie Bow killed at the start of Slow Horses' second series?

Poisoned by an old enemy: Bow tailed a Russian who had tortured him in the Cold War, and his death was first ruled a heart attack.

Which private security firm is at the centre of Slow Horses' third series?

Chieftain, run by Home Secretary Peter Judd's old friend Sly Monteith, is hired as a 'tiger team' to test MI5 by kidnapping Standish.

In which city does Slow Horses' third series open, as MI5 officer Sean Donovan tails his lover?

Istanbul, where Donovan loses track of his lover Alison Dunn just before she hands over a stolen embassy file and is murdered.

Who plays London mayor Zafar Jaffrey in Slow Horses' fifth series?

Nick Mohammed, Ted Lasso's Nate, plays Jaffrey, whom Shirley and Standish guard when terrorists try to assassinate him.

Which Slough House novel did Slow Horses' second series adapt?

Dead Lions was the sequel that Slow Horses' first UK publisher refused after poor sales, so at first it came out only in the US.

What falls on populist mayoral candidate Dennis Gimball's head, killing him, in Slow Horses' fifth series?

A paint can kills Gimball by accident, but his habit of taping everything later hands Lamb the recording that forces Whelan to resign.

What does Lamb leave the unmasked spymaster Katinsky in Slow Horses' second-series finale?

A single bullet, which Katinsky, exposed as the legendary spymaster Popov, uses on himself.

In Slow Horses, MI5's headquarters goes by the name of which London location?

Regent's Park, or 'the Park', is where River sneaks in during series 1 to steal the photo that exposes Taverner's plot.

What does Roddy Ho crash through a house, too late to rescue anyone, in Slow Horses' third series?

A bus: Roddy rams a hot-wired double-decker into the house to save Lamb and Standish, but the attackers are already dead.

In Slow Horses' fifth series, Lamb tells a gripping story about a spy tortured by which secret police?

The Stasi tortured the spy in Lamb's tale, which holds his captors so rapt that his agents manage to overpower them.

What production habit lets Slow Horses release a new series almost every year?

Shooting two runs back to back means the next series is already filmed by the time the current one airs.

Who is shot dead defending Slough House at the end of Slow Horses' fourth series?

Marcus Longridge dies in a shootout with the assassin Patrice, and grief over him haunts Shirley in series 5.

Which London Zoo animals are targeted by a terrorist bombing in Slow Horses' fifth series?

Penguins are hit as one step in a terror cell's plan to destabilise London before assassinating a politician.

In Slow Horses' fourth series, which country does River travel to under a dead assassin's identity?

France: River takes the identity of the assassin his grandfather shot and follows a café receipt to the town of Lavande.

Why was Sid Baker placed in Slough House in Slow Horses' first series?

To keep an eye on River, as Sid admits to him just before a masked gunman shoots her in the head.

Near which tube station is Slough House located in Herron's novels?

Barbican is a stone's throw away: Herron put Slough House on Aldersgate Street, in a building he walked past on his way to work.

What blunder got River Cartwright sent to Slough House in Herron's novels?

Shutting down King's Cross station was River's blunder in the books, which leaves him desperate to clear his name.

Which award did Herron's second Slough House novel win in 2013?

Gold Dagger: Herron won the Crime Writers' Association award, yet his books only began selling after a 2017 bookshop promotion.

Which bookseller named Slow Horses its "thriller of the month" in August 2017?

Waterstones picked it seven years after the novel flopped on release, and Herron calls himself 'a rescue author'.

Who throws boiling water at the assassin storming Slough House in Slow Horses' fourth series?

J.K. Coe goes on to work out a terror cell's whole destabilisation plan in series 5.

What event shifted Herron from detective to spy fiction?

The 7 July 2005 bombings struck as Herron was travelling to work, showing him that simply being in a city puts you on the front line.

Herron has no intelligence background, so what was his day job before he wrote full time?

Subeditor on a law journal: Herron says subediting taught him precise, economical language, and he wrote for an hour each evening after commuting home.

Which Herron novel became a 2025 TV series starring Emma Thompson as private investigator Zoë Boehm?

Down Cemetery Road follows a neighbour who hires Zoë after a girl vanishes when a house explodes in an Oxford suburb.