Slow Horses features several MI5 agents whose abilities and skills vary drastically. The central premise of Slow Horses is that a group of problematic MI5 operatives have been ousted from the organization, but against the odds, they manage to succeed and often outshine the agency that shunned them.
The so-called “Slow Horses” operate out of Slough House with minimal oversight or support from MI5. This exile came about due to the agents being involved in a range of inappropriate behaviors, from being socially inept to drug abuse, or even catastrophic failure in previous missions.
However, the Slough House team does manage to pull off some big wins despite the opposition and occasional tampering from their peers at the Park. Still, some agents certainly stand out more than others.
Claude Whelan
Claude Whelan is not a member of Slough House, in fact, he is the First Desk, or Head of MI5. Despite this fact, Whelan seems completely out of his depth in his new role. Whelan replaced the former First Desk, Ingrid Tearney, thanks to his connections in government.
Previously, Whelan served as an advisor and consultant on various security teams, but his ascent to becoming the Head of MI5 was inarguably too much, too soon. Whelan hoped to change the organization and harbor a culture of honesty and truth, but his sensibilities quickly crumbled when he landed in hot water.
Whelan is easily the worst operative in Slow Horses, with no apparent expertise apart from forming connections, and a lack of understanding of the basics of espionage and security.
Roddy Ho
One step above Whelan stands Roddy Ho, the tech expert at Slough House. Roddy has incredible computer skills, and he can hack systems and pull off complex maneuvers online, but when it comes to anything physical, Roddy is hopeless.
Pair this with the fact that Roddy has an extraordinary ego and the result is an agent who thinks he is so much more important than he truly is, and frequently overstates his abilities. Roddy is at least useful when it comes to navigating the digital space, but it makes sense that he wound up in Slough House.
Diana Taverner
Back to the Park, Diana Taverner is the Second Desk at MI5. Diana is ambitious, ruthless, and calculating. This means that she is often able to meet her goals through whatever measures are required, but it also results in a flexible moral character that causes more problems.
Diana and Jackson Lamb have a comfortable relationship as they understand one another and choose to avoid getting mixed up, but Diana’s ambitions have often led to her trying to shift the blame onto others like Tearney or Slough House.
Diana’s sly and calculating nature, combined with her high rank, mean that she is a powerful ally, or rival, depending on the circumstances. However, the fact that she is primarily concerned with her own best interests presents a threat to anyone that might stand in her way.
Shirley Dander
Shirley Dander is one of the most recent recruits at Slough House, having been ousted from the Park due to her drug habits. Under the influence, Shirley is a shaky mess who is unable to get anything done, but with a clear head, she has good instincts.
It was Shirley that was able to see when Roddy was being targeted before anyone else, and Shirley has successfully managed to repel attacks from highly skilled assassins, walking away with only minor injuries. However, Shirley has struggled to actually apprehend and capture her targets on numerous occasions.
Catherine Standish
Catherine Standish is one of the most senior members of Slough House, and a faithful ally to Jackson Lamb. For years, Standish has served as his receptionist and personal aide, and before Lamb, she played a similar role for a former First Desk of MI5, Charles Partner.
While Standish is not technically an operative who is supposed to work in the field, her years of experience have prepared her to deal with difficult situations and notice when things don’t add up. Standish is often a wild card whose skill is surprisingly refined.
As a result, she is often an essential part of any operation from Slough House. However, the lack of field experience means that she is trailing behind some of the younger and more adaptable agents of MI5.
Emma Flyte
Emma Flyte is the Head of Security at MI5, and the leader of the group known as the Dogs. Emma is a relatively young agent in the service, but she has an impressive track record, having climbed the ranks and earned her position through hard work and dedication.
Emma appears to avoid playing around in political games like Diana Taverner. However, she remains fiercely loyal to the leadership of MI5 and is more than happy to put a muzzle on Slough House when they step out of line.
Despite all of this, it does seem like Emma has the necessary skills to be a major force in MI5, and recognizes that the vendetta against Slough House is misplaced. She remains in her position due to her willingness to obey orders without thinking independently, despite recognizing potential injustice.
River Cartwright
On the complete other side of that scale, there is River Cartwright. River’s grandfather, David Cartwright, was a high ranking member of the service, and River had high aspirations to follow in his grandfather’s footsteps. However, when River was set up to fail catastrophically in a mission, he was exiled to Slough House.
River has shown exemplary skills in all areas of spycraft, though his fatal flaw is his ego and a lack of ability to work in a team setting. River gets an idea, and he runs with it, with little thought about the consequences, largely working on intuition until he can gather the evidence to prove a theory.
His exceptional skills earn him this spot on the list, but if River Cartwright could refine his teamwork and take a moment before running head first into trouble, he has the potential to climb even higher.
J.K. Coe
Until then, J.K. Coe, the most recent newcomer at Slough House, stands out as the top operative. While Coe’s reason for being sent to Slough House has not been explicitly revealed in the TV series, it seems as though his socially awkward behavior may have been a contributing factor.
After all, a spy should be able to navigate complex social situations and control the room. However, despite a lack of social skills, Coe’s intuition, intelligence, and stealth are extraordinary. Coe is able to see patterns where others can’t, and make sense of chaos.
In addition, Coe is incredibly well-prepared, bringing whatever tools he may need to complete a job quickly and efficiently. Yes, he makes some wild mistakes at times, but his basic instincts are all there, and he’s one of the best agents to ever work at Slough House.
Jackson Lamb
But standing tall at the top of the hill is Jackson Lamb, the legendary agent of MI5 and now head of Slough House. Lamb has the most field experience of anyone on this list by far, and he has been responsible for pulling off some of the biggest and most secretive missions MI5 has ever been involved in.
Having served faithfully for decades, Lamb was allowed to choose any position to be assigned to in his final years in the service before retirement, and bewilderingly, he chose Slough House. As it turns out, Lamb is managing to single-handedly turn Slough House into a functional unit, though it’s still not perfect.
Lamb also tends to keep his guard up and avoid creating close emotional bonds with his team. On the surface, Jackson Lamb looks like he’s a miserable and cruel old man, but the reality is he is someone who is deeply concerned with his team’s success. All of which adds up to making him the best agent in Slow Horses.
