Every Slow Horses Book in Order, and the Season Each One Became

The book that introduces Slough House, the dead-end department where MI5 parks the agents it cannot fire, and the crew of burnouts stuck there under Jackson Lamb. River Cartwright, exiled after a training exercise goes badly wrong, is doing pointless make-work when a young man is kidnapped on camera by a group threatening to behead him on a livestream. What looks like a far-right terror plot pulls the slow horses off the sidelines and into something with far more going on beneath it, and the case keeps shifting under them as Lamb’s people turn out to be sharper than their reputations. Season 1 of the show is built on it.

• Slow Horses (Book 1): Audiobook | Hardcover | Paperback | Kindle

An old Cold War spy is found dead on a bus outside Oxford, written off as natural causes until Jackson Lamb, who knew him, decides otherwise. The thread leads back to a network of Russian sleeper agents, the “cicadas,” planted in Britain decades ago and long thought dormant. While River is sent into the field to chase a ghost from the past, Lamb works the case from his own buried history in the service, and the two strands close in on a long-dormant operation waking back up. The show’s second season follows it.

• Dead Lions (Book 2): Audiobook | Hardcover | Paperback | Kindle

Catherine Standish, Lamb’s quietly capable assistant, is snatched off the street, and the kidnapping turns out to be leverage. Her captors use her to force River into breaking into MI5 headquarters and stealing secret files, while a power struggle at the top of the service, with the ambitious politician Peter Judd pulling strings, threatens to swallow Slough House whole. The slow horses, more loyal to each other than to anyone above them, break every rule to get one of their own back. The show’s third season is drawn from it.

• Real Tigers (Book 3): Audiobook | Hardcover | Paperback | Kindle

River’s grandfather, the retired spymaster David Cartwright, once one of the most powerful men in the service, is slipping into dementia, and the secrets locked in his failing memory make him a danger to himself and everyone around him. When a bombing in a London shopping center sends River chasing a lead that runs back toward his grandfather’s past, he finds the old man’s history harder to leave alone than anyone wanted. Season 4 adapts this book.

• Spook Street (Book 4): Audiobook | Hardcover | Paperback | Kindle

A string of seemingly random attacks across the country turns out to be following a playbook, an old MI5 contingency plan for destabilizing a nation, now being run against Britain itself. As the slow horses work out who is holding the script, a populist MP and a scandal-prone government drift into the frame, and the satire sharpens. Roddy Ho, the team’s insufferable hacker, gets pushed to the front this time, with someone targeting him directly and the rest of the team reluctantly closing ranks around him. The show’s fifth season takes its story from here.

• London Rules (Book 5): Audiobook | Hardcover | Paperback | Kindle

“Joe country” is field slang for hostile territory, and the team ends up deep in it when a connection to a dead colleague pulls them into the snow-covered Welsh hills in the dead of winter. What starts as a search turns into a fight for survival against an enemy who knows the ground better than they do, the cold and the terrain as much a threat as the guns. Season 6 adapts this book together with the next one, Slough House, blended into a single story, running from September 16 to October 21, 2026. Apple has said the season turns on Diana Taverner pulling the team into a game of retaliation and revenge that puts them on the run.

• Joe Country (Book 6): Audiobook | Hardcover | Paperback | Kindle

In a paranoid, post-Brexit Britain, Slough House is being quietly deleted: its budget cut, its name scrubbed from the records, as if the department and everyone in it never existed. At the same time, a new threat surfaces that puts the slow horses squarely in someone’s sights. Lady Di Taverner’s secret funding deal with a corrupt politician has come back to bite, and the team has to fight just to stay alive and on the books. Season 6 adapts this book alongside Joe Country.

• Slough House (Book 7): Audiobook | Hardcover | Paperback | Kindle

A government superforecaster, part of a think tank advising Downing Street, has gone missing, and a slippery prime ministerial adviser is clearly steering events from the shadows. Underneath it runs a thread of Russian disinformation and a sleeper agent buried inside the British establishment, with Lamb and his crew pulling at threads everyone above them would rather leave alone. Spin, leaks, and the people who manufacture reality for a living all come into play as the team works out who is really running the operation. Confirmed as the basis for Season 7, which Apple has renewed for 2027.

• Bad Actors (Book 8): Audiobook | Hardcover | Paperback | Kindle

The newest novel in the series, following Bad Actors. River digs into his late grandfather’s library and a single book that has gone mysteriously missing, a thread that leads back into a Troubles-era cover-up the service would rather have stayed buried. Diana Taverner, never one to waste leverage, sets about turning that old secret into blackmail. The slow horses are caught in the middle as the past and present collide again, in a story that ties the long-running threads of the series tighter. It has not been adapted yet, sitting two seasons ahead of where the show currently is.

• Clown Town (Book 9): Audiobook | Hardcover | Paperback | Kindle

Dieter Hess, an aging spy, is dead, and his MI5 handler John Bachelor has to work out whether Hess was a double agent after a secret second bank account turns up in his name.

• The List: Audiobook | Paperback | Kindle

Retired agent Solomon Dortmund witnesses what looks like a dead drop in a Marylebone cafe. Reporting it to John Bachelor, who looks after retired spies for MI5, sets off a chain of events neither man expected.

• The Marylebone Drop: Audiobook | Paperback | Kindle

John Bachelor has been living rent free in a dead spy’s London flat while his career, marriage, and savings have all quietly fallen apart. Keeping that quiet among spies turns out to be impossible, and he ends up eminently blackmailable.

• The Catch: Audiobook | Paperback | Kindle

The Last Dead Letter (2020): Archivist Molly Doran summons Jackson Lamb to St Leonard’s, the Spooks’ Chapel, and gets him to fill in the last details of a Cold War Berlin story she has mostly already pieced together.

Standing by the Wall (2022): A Christmas Eve interlude. Lamb hands Roddy Ho the job of erasing a man from an old photograph, and the tedium of the task pushes Roddy into a rare moment of reflection on his own place in the world.

Neither has a standalone edition. This collection, which also includes The List, The Marylebone Drop, and The Catch, is the only way to get either one.

• Standing by the Wall: Audiobook | Paperback | Kindle