The episode opens with a man leaving his apartment and sitting opposite a political campaigner in a town setting. He is then interrupted by a honking van, from which he retrieves a bag and heads toward the Abbotsfield Shopping Centre. This man proceeds to carry out a mass shooting inside the shopping centre, killing and injuring many people indiscriminately. The scene is chaotic and grisly, with the shooter methodically firing at bystanders. After the shooting spree, the shooter is killed by an unknown man who appears suddenly and shoots him dead, ending the attack.

Meanwhile, at Slough House, the MI5 team is dealing with the fallout from the shooting and the tense political atmosphere it has created. Jackson Lamb and his team are on edge, especially as the shooting is linked to broader political tensions involving immigration and radicalization. The agents are still recovering emotionally and professionally from the previous season's events, and there is a palpable sense of unease about what is to come.

Jackson Lamb and Diana Taverner, MI5's second-in-command, put Slough House on lockdown due to suspicions surrounding Roddy Ho's personal life. They are concerned that Roddy's new girlfriend might be involved in the terrorist activities linked to the shooting. Both Lamb and Taverner are wary and keep a close watch on Roddy, suspecting that his relationship could be a cover for something more sinister.

At an office party for Slough House, Louisa is the guest of honor as she prepares to take a six-month mental health break. The party quickly sours when River makes an insensitive comment about Shirley's inability to cope with Marcus's death, causing tension and awkwardness among the team. Jackson retreats to his office with a bottle of cheap Scotch and a Slinky cake, finding some solace away from the uncomfortable gathering.

Later, River and Shirley end up at a nightclub, which they feel is too old for them, to surveil Roddy and his new girlfriend. They suspect the girlfriend is an operative working for an unknown malicious party, possibly linked to the recent attacks. Shirley, in a moment of confusion and paranoia, leaps from a nightclub balcony onto a server she mistakes for an assassin, highlighting the team's general ineptitude and heightened anxiety.

Emma Flyte, head of the Dogs (a more elite MI5 unit), notices that the sniper who killed Trew used a 7.62 caliber bullet. This detail suggests that the person who pushed Trew to take drastic action is also the one who ultimately killed him, indicating a deeper conspiracy at play.

Throughout the episode, the Slough House agents grapple with the political implications of the shooting, the threat of further attacks, and their own personal vulnerabilities. The episode ends with the team on high alert, aware that one of their own may be in danger, and that the political and terrorist threats they face are more complex and dangerous than ever.

The ending of Slow Horses Season 5, Episode 1 ("Bad Dates") reveals that Rob Trew, the perpetrator of a mass shooting at Abbotsfield Shopping Centre that killed 11 people, was not acting solely out of personal anger or extremist ideology. Instead, his attack was part of a larger, more complex political conspiracy linked to the upcoming London mayoral election. Before he could fully expose the truth behind his motives, Trew was silenced, leaving Slough House agents facing a tangled web of mistrust and hidden agendas.

The episode concludes with a tense and unsettling sequence that unfolds as follows:

The scene opens in the aftermath of the Abbotsfield Shopping Centre massacre, where emergency services and investigators swarm the area. The death toll is confirmed at 11, with several others wounded. The initial assumption is that Rob Trew, a middle-aged man with far-right sympathies, carried out the attack driven by extremist political beliefs. Evidence found in his apartment includes books by far-right candidate Dennis Gimball and a photograph linking Trew to the politician, suggesting a politically motivated rampage.

However, as Slough House agents dig deeper, it becomes clear that Trew's actions were not simply those of a lone extremist. The narrative reveals that his mass shooting was orchestrated within a broader political scheme, implicating powerful figures who benefit from the chaos. This is underscored by the discovery of a second shooter--a sniper--indicating a coordinated attack rather than a spontaneous act of violence.

Meanwhile, the team at Slough House is on edge. Jackson Lamb continues to manage his flawed but capable agents, who are grappling with the fallout of the attack and the suspicion that one of their own, Roddy, may have been the target of an attempted hit. Louisa, another key agent, announces her decision to leave Slough House and the intelligence service altogether, seeking distance from the toxic world of espionage.

The episode closes on a somber note, with the agents reflecting on the brutal reality of their work. The political intrigue and violence have shattered any illusions of safety or straightforward justice. The final moments emphasize the theme of "London Rules"--a ruthless environment where everyone must look out for themselves, and trust is scarce.

In terms of character fates at the episode's end:

• Rob Trew is dead, his violent act having unleashed a political storm but leaving many questions unanswered.
• Jackson Lamb remains the steady, if gruff, leader trying to hold his team together amid chaos.
• Roddy survives but is under suspicion and threat, his safety uncertain.
• Louisa departs from Slough House, seeking a fresh start away from espionage.
• The rest of the Slough House team is left to navigate the dangerous political fallout and the murky loyalties that define their world.

This ending sets the tone for a season steeped in political conspiracy, personal betrayal, and the harsh realities of intelligence work.

There is no indication of a post-credit scene in Slow Horses Season 5, Episode 1. The available detailed recaps and analyses of the episode do not mention any post-credit or after-credits scene. The episode ends with significant plot developments, including Shirley's confirmed suspicion that Roddy is in danger and the revelation about his suspicious new girlfriend, but no additional scene after the credits is reported.

Shirley suspects that someone intentionally tried to run over Roddy, and her investigation into security footage and a suspicious white van confirms that Roddy is indeed in danger. This suspicion is validated by the episode's end, revealing a subplot involving Roddy's mysterious girlfriend who may be involved in a plot against him.

The episode opens with a shocking mass shooting in a public market square, which sets off a politically charged conspiracy that forces Jackson Lamb and the Slough House team back into action.

Roddy is shown dating a woman who is suspiciously attractive and possibly involved in malicious activities. His colleagues find it hard to believe he has a genuine relationship, leading to surveillance and suspicion that she might be working against him.

The episode introduces a political conspiracy linked to a violent terrorist attack during the mayoral election campaign, highlighting themes of government corruption and political intrigue as central to the unfolding plot.

The agents, including Jackson Lamb, River, and Shirley, are drawn out of their uneasy peace to investigate the mass shooting and the attempt on Roddy's life, combining their usual mix of incompetence and dedication to uncover the truth behind the political and personal dangers they face.

The TV show Slow Horses, including Season 5 Episode 1 (2025), is not family friendly and is generally intended for mature audiences.

Potentially objectionable or upsetting content includes:

• Strong and frequent profanity, including numerous uses of the f-word, s-word, and other harsh language and racial slurs.
• Moderate to graphic violence, including bloody gunshot wounds, fight scenes, and some graphic depictions of violence.
• Mild sexual content and nudity, such as scenes in an adult toy store, brief underwear exposure, and passionate kissing.
• Alcohol use and smoking are depicted moderately throughout the series.
• Dark, bleak tone with intense and suspenseful scenes that may be unsettling for sensitive viewers.

Overall, the show contains mature themes, explicit language, and violence that make it unsuitable for children or sensitive viewers.