Find even more on the slow horses and the Slough House series here.

There is a lot going on in Mick Herron’s Slough House books and following the tradition of John le Carré he’s created his own spy jargon. As the series continues I thought having a cheat sheet might prove helpful for refreshing memories as we return to the series after a break between books.

Also, as the series has progressed, I’ve become more and more fascinated by the structure of Herron’s fictional MI5. At the very bottom of the glossary, I’ve included a potential organizational chart based on hints that Herron has dropped throughout the series.

Please know that I’ve tried to shy away from too many spoilers but given the way Slough House goes through agents, there’s a certain amount that will slip through. If you haven’t read all of the books, proceed with caution. I’ve made major spoilers hidden. Highlight the white space before the parentheses to see them.

Catch up on all the latest news on the upcoming Apple TV series – SLOW HORSES here.

Read reviews of each of the Slough House books, an interview with Mick Herron and more I’ve written on the Slough House series here.

The term or person’s first book appearance will be in parentheses.

Reconstruction (R)

Slow Horses (SH)

Dead Lions (DL)

The List (TL)

Nobody Walks (NW)

Real Tigers (RT)

Spook Street (SS)

London Rules (LR)

The Drop (TD)

Joe Country (JC)

The Last Dead Letter (TLDL)

The Catch (TC)

Glossary

Abbotsfield – The village that becomes an unlikely terrorist target. (LR)

The Achievers – The men who break down doors, break noses, and generally take care of all of the Services breaking needs. The boots on the ground. (DL)

Across The River – Where the analyst types in MI5 live. (SH)

AFM – Anger Fucking Management (SH)

Ahmed,  Hassan – Aspiring comic, college student, nephew of Pakistani Intelligence bigwig, kidnap victim. (SH)

Aldersgate Street – The street in the Barbican on which Slough House is located. (SH)

Bachelor, John – A babysitter for old assets, he finds himself in the soup when one of his charges turns up dead. (TL) Later his life slides further down the pole as he’s left living out of his car. (TD)

Background – The section in charge of vetting for MI5. (DL)

Baker, Sid – A young, attractive agent who is sent to the slow horses for murky reasons. Injured in the line of duty and spirited to parts unknown. (SH)

Black Ribboned – MI5 uses a black ribbon to tie off closed files. Also used as a euphemism for the shipping off of folks to secret black sites in Europe which is the rumored way MI5 gets rid of it’s internal and external personnel problems. (LR)

The Beast – Refers to the various informational digitized databases MI5 keeps. The opposite of Molly Doran’s hardcopy domain. (LR)

Beattany, Tom – Former undercover MI5 agent, former faux-criminal, former Dog, former butcher, former husband, former father. Currently a man with nothing left to lose but whatever little bit of his soul he has left. Probably ends up Black Ribboned or dead in a ditch. (NW)

Bradley, Leonard – Previously the head of the Limitations Committee. Removed when it was found a “safe house” he’d funded was really a “beachfront property on the Maldives.” (SH)

C&C – Collect-and-Comfort, the practice of picking up a subject of interest and holding them offsite and out of sight until needed. (R)

Cartwright, David – Known as the power behind the throne in his time at MI5 in the 70’s and 80’s. Now known as the “OB”, Old Bastard. (SH)

Cartwright, Isobel – River’s mother. Wannabe free spirit. (SH)

Cartwright, River – Young, white, fair hair, grey eyes and a mole on his upper lip. Wannabe super spy/espionage royalty/screwup. In the first book his bungled call on a potential terror incident landed him on the slow horses where he’s been trapped ever since. (SH)

Chapman, Bad Sam – Formerly the Head Dog who had a large amount of money go missing on his watch. Ends up working for an agency that tracks down runaways. He first appears in Reconstruction trying to salvage a screw up before being bounced from the Service. Meets a bit of a sticky end at Slough House. (R)

Coe, JK – Banker turned member of MI5, he’s a babe in the woods compared to cynicism and wiliness that his colleagues show. Sent to the slow horses by Dame Ingrid to hide one of her messy mistakes. Coe learns the hard way that “Kill the messenger” is not just a turn of phrase when you work for MI5. Full name, Jason Kevin. After a trauma he finds the one thing that works best to take the edge off is … murder? (TL)

Cold body – A set of identity papers that is ready to be used and rock solid. Typically created years before they are needed. (LR)

Comms – Also know as Comms and Surveillance. (SH)

The Cotswolds – Far from London, this is the area where River goes undercover in to find a mysterious Russian agent. (DL)

Crane, Amos – Old MI5 hand that is described as “fox turned henhouse warden” and later according to Lamb – “some chick whacked him.” (DL)

Critical Mass – The spy thriller that River Cartwright is supposed to have written when he is undercover as Jonathan Walker. (DL)

Cross, Dominic – Pseudonymous name created by Molly Dornan given to a compromised agent in Berlin before the fall of the wall. (TLDL)

Dancer, aka Reginald Blaine – Sketchy character who works out of a stationery shop but can also provide IDs and weapons if needed. (NW)

Dander, Shirley – Short and built like a barrel. A new slow horse who gets a high from doing her job, also from cocaine. Partners up with fellow slow horse Marcus Longfellow. Former member of Comms department. Sent to Slough House after punching a colleague. (DL)

The Dentists – The MI5 interrogators who go to work in the deniable basement interview rooms. (DL)

The Dogs – MI5’s internal investigation unit. They keep the MI5 employees in line and sweep their errors under the rug. Don’t end up in the lower level in one of their “interview” rooms. (SH)

Doran, Molly – Old MI5 hand who lost her legs at some point in the 90’s. Knows where the bodies are buried. Keeper of the secrets that MI5 prefers to stay buried, she seems to live in the basement of Regents Park with her files. (DL)

Dortmund, Solomon – Older spy living out his retirement days in London. (TD)

Dosshouse – A flop house or cheap place to stay.

Down the Corridor – Refers to the politicians in Westminster. (SH)

Driscoll, Victor – Odd duck, “tender plant” and millionaire software developer who Tom Beattany suspects may have caused the death of his son Liam. (NW)

Duffy, Nick – One of the Head Dogs. Willing to do whatever his bosses need, no questions asked. Not a fan of River Cartwright and should either wear a helmet or stay away from lead pipes. (SH)

First Desk – The Head of MI5. Constantly thinking about how to out maneuver the politicians “Down the Corridor” and their own staff. (SH)

Fischer’s – An Austrian restaurant in the London neighborhood of Marylebone. It ends up being the location of a spy meet between a handler and his agent. (TD)

Flight Fund – A secret stash of money that most agents hide away in order to make a run for it if things get too hot. Usually accompanied by a fake passport.

Flyte, Emma – One of the Head Dogs. Came from the Met and is jaded against spy shenanigans. Also model level beautiful. Eventually sent to the slow horses and doesn’t make it out alive. (SS)

Grey Books – Also known as the “whackjob files.” The files that the government keeps on every crazy conspiracy theory. (RT)

Guy, Louisa – Louisa was sent to the slow horses after she lost a suspect she was supposed to be tailing and a bunch of illegal guns ended up on the streets of London. She’s surprised when her relationship with Min Harper gives her a purpose and strength she forgot she had. Probably the most competent of the slow horses. (SH)

Harkness, Frank – Ex-CIA agent who has gone rogue with his own agenda. Has a surprising connection to a slow horse. Harkness is revealed to have run a school for spies, tasked with creating it’s own version of terrorists to test out potential terrorist acts. Gets funding from David Cartwright as a way to keep him away from his daughter Isobel. Harkness also turns out to be River’s father. (SS)

Harper, Min – Min ended up on the slow horses after leaving a top secret disk on the train. Sees an assignment from the untrustworthy “Spider” Webb as his way back into the big leagues.Two spy screw ups who form an unlikely connection. Meets a bad end at the hands of 2 russians. (SH)

Henderson, WW – Name lettered on window of River Cartwright’s office. Says “WW Henderson, Solicitor and Commissioner for Oaths” (SH)

Hess, Dieter – Retired Cold War asset, currently deceased. Still managing to cause heartburn for his handler. (TL)

Ho, Roddy “Clint” – Computer genius and social incompetent. Hacking skills – 99%, People skills – 1% Only thing keeping his people skills from rating a 0% is the existence of someone with even less. See “Jackson Lamb” Sent to the slow horses not because he did anything wrong but because no one can stand to be around him. (SH)

Hobden, Robert – Former reporter for the Telegraph turned columnist. Former leftwinger turned rightwing. When his membership in a far right, white supremacist organization was outed, he lost whatever influence he once had. (SH)

The Hub – Diana Taverner’s home base. The various operations agents and analysts work in cubicles here. Taverner’s office has windows that overlook the room. (SH)

“joe” – An agent. (SH)

joe country – Term used when an agent is out in the field on assignment. (SS)

Judd, Peter – Back bencher turned Home Secretary. His plans to become the new PM do not end up going in his favor. (SH)

The Kennel – Office space of MI5 internal security force, the Dogs. (RT)

Kim – Roddy Ho’s fabled “girlfriend” (SS)

Kreutzmer, Martin – A member of the German spy agency running Hannah Weiss and he’s not afraid to get his hands dirty to keep his agent free and clear. (TMD)

Kyril – One of a pair of Russians working for Arkady Pashkin. (DL)

The Last Dead Letter Drop – The wall in St. Leonard’s filled with plaques as a memorial to those spies who died in the line

Lamb, Jackson – The famous, or infamous depending on who you ask, Cold War spy. A Cold Warrior whose closest brush with being PC was turning on a computer. Never found a nap not worth taking, belch not worth belching or fart not worth letting loose. The improbable creator and head of Slough House. Worked as a mirror-man in Berlin during the Cold War. Slough House was created at his request for him to run after he killed Charlie Partner for MI5 to hide the fact that he was a mole for the Russians. (SH)

Les Arbres – Base of operations for Project Cuckoo. (SS)

Limitations Committee – Former Steering & Oversight, the committee with financial oversight of MI5. Chaired by Leonard Bradley, then Oliver Nash. (TL)

London Rules – The rules for survival in the MI5 bureaucracy –

Rule #1. “Cover your arse.” (SH)

Rule #2. “… [F]orce others to take you on your own terms. And if they didn’t like it, stay in their face until they did.” (LR)

Rule #3. “[A]lways be a fair distance from a fuck-up.” (TC)

Longridge, Marcus – Bald with goatee, Black, carrying a few extra pounds. Special operator and potential plant in Slough House by the politically wily Diana Taverner. (DL)

Loy, Struan – A slow horse, single and with few prospects until Diana Taverner dangles a lifeline. (SH)

Manors, Benny – 40’s with a limp. Small time thief and blackmailer whose skills were enlisted by the service. His service to the service is how he received the aforementioned limp. (TC)

Marta – East German living in West Germany. Has a son named Edward and makes the mistake of having an affair with an MI5 agent. See Cross, Dominic. (TLDL)

MI5 – The security service.

milkman – A “retirement needs evaluation counselor” otherwise known as a babysitter of former spies living out their remaining lives wherever MI5 resettled them. See Bachelor, John (TL)

mirror-man – A sort of spy supervisor who receives updates from agents on encounters with the opposition. (TLDL)

Moody, Jed – A former “Dog”, Herron’s name for MI5’s internal affairs/cleanup squad, now put out to pasture with the Slow Horses. (R)

Moscow Rules – The Rules for survival in Cold War Moscow, the main one which is – “Watch your back.” See here for more. (SH)

Nash, Oliver – Head of the Limitations Committee. Lifelong soldier in the battle of the bulge. Went to London School of Economics. (TD)

The Needle – The latest and greatest tall building in London and the location of a meeting between Arkady Pashkin and Spider Webb. (DL)

Ops – The area that runs agents for MI5. Based out of the Hub. (SH)

Palmer, Digby – Agent in Berlin before the fall of the Wall. Lost his love and killed himself in less than a year. Given the choice between betraying his agent Atticus or Lover Marta, chose Marta, only to have Jackson Lamb stop the betrayal. See Cross, Dominic. (TLDL)

Partner, Charles – Former First Desk found dead in his bathtub by his assistant Catherine Standish. Later found to have been a Russian mole. (SH)

Pashkin, Arkady – A Russian oligarch that is interested in a potential partnership with the UK. Turns out to actually be running a scam to steal diamonds from a jeweler in the Needle. (DL)

Pynne, Richard – AKA “Dick the Prick” and up and comer in Ops. His first job as handler is a German double agent. Wears glasses and a receding hairline led to shaved head and going to Cambridge. (TD)

Pitor – One of a pair of Russians working for Arkady Pashkin. (DL)

Pointer, Francis “Flea” – Naive and sentimental friend of Liam, Tom Bettaney’s son. (NW)

Popov, Alexander – A former KGB officer that’s more ghost than reality. (DL)

Project Cuckoo – A seriously crazy plan to create your own terrorists so you know how a terrorist would think. Not one of the intelligence world’s better ideas. (SS)

Psych-Eval – Area of MI5 that evaluates potential operations for their psychological effect as well as offers analysis of agents and targets. Part of the Weasels and formerly JK Coe’s stomping grounds. (NW)

Queens of the Database – Gatekeepers for all of MI5’s data. Anything digital goes through them. Falls under Comms and Surveillance. (R)

Regent’s Park – The main location of MI5. The Holy Grail for all Slow Horses. (SH)

Second Desk – There are five of these positions in charge of various areas in MI5 that report directly to the First Desk. (SH)

Slough House – Located on Aldersgate street right next to Barbican Station in London. It was created at Jackson Lamb’s request after he did the dirtiest of dirty work for MI5. (SH)

Snow White – Operation to have a German double agent. (TD)

Spooks’ Zoo – Berlin. So called because of the many species of spies present. (TLDL)

Stagge, Helmut – Hard bitten agent of the Stasi. Brown eyes, brown raincoat, probable brown soul. (TLDL)

Standish, Catherine – Formerly the right hand of the head of the service, formerly a drunk, currently sober and the administrative force keeping Lamb’s Slough House running. Personally recruited to the slow horses by Lamb, perhaps as penance. (SH)

St. Leonard’s – The small church in Hampstead surrounded by a tall hedge that is only used for the discrete funerals of ex-spies. Also known as St. Len’s or Spooks’ Chapel (JC)

Stoats – Watchers. Agents performing surveillance on a target. (SS)

Streetwalker – Similar to a stoat. Someone who follows a target. (DL)

Taverner, Diana aka “Lady Di” – MI5 upper management. I was going to call her a schemer, but since everyone in these books seems to be scheming in some way, that doesn’t seem entirely fair. Better might be that she raises scheming to an artform. She keeps a finger on all the plotters plots at MI5 with the hope that one of them will propel her to the top job. The iron fist of MI5 who is missing her velvet glove. (SH)

Tearney, Dame Ingrid – Head of MI5 and someone with so many nefarious plans in the air she could join the circus as a juggler. Forced out after causing a London shoot out in Dead Lions. (NW)

Tiger Team – A group that tests for holes in an organization’s security measures. (RT)

Tregorian, Moira – Office administrator bewildered she’s been sent to live with the slow horses. (SS)

Voices of Albion – Right wing group responsible for the kidnapping of a young man to make a political point. (SH)

Walker, Johnathan – Cover name of River Cartwright while in the Cotswalds. (DL)

Watering Hole Paper, The – Refers to a old MI5 plan on how to destabilize a third world country. Later repurposed for nefarious means. (LR)

Wants & Needs – Also known as “Whines & Giggles”

The Weasels – The analysts who crunch the numbers to guess at what real world outcomes of various MI5 machinations might be. They live across the river from Regent’s Park. (SS)

Webb, James “Spider” – The jealous peer of River and aspiring bigwig, currently littlewig. Schemer and dreamer who unrealistically sees himself climbing the ladder past many people much better at scheming than him. See “Diana Taverner” (SH)

Whelan, Claude – Head of MI5. Dropped in as a “safe pair of hands” after the last debacle. Diana Taverner takes him under her wing with the phrase “friends close, enemies closer” in mind, but he has his own skeletons in his closet. Forced out after revealed to be the partial cause of the terror events of London Rules. (SS)

Weiss, Hannah – A triple agent for Germany who proves able to lead her MI5 handler by the nose. (TL)

Welles, Devon – Emma Flyte’s right hand and another Met transplant. (LR)

Westacres – Site of a terror attack on a mall. (SS)

White, Kay – A slow horse dropped a lifeline by Diana Taverner. (SH)

Wicinski, Alec “Lec”– MI5 analyst who learns the hard way that no good deed goes unpunished. Sent to the slow horses after learning too much about a German spy. Won’t be working as a model anytime soon. (TD)

Potential “Slough House” series MI5 organizational chart