The episode opens with River Cartwright abruptly leaving Slough House and sprinting toward a bridge in London. Upon arrival, he encounters James "Spider" Webb, who is visibly distressed and reveals he is being blackmailed by unknown kidnappers. Spider delivers a dire message: River must retrieve the Prime Minister's vetting files from Regent's Park by midday, or Spider's family will be killed. To underscore the seriousness, a laser pointer is aimed at Spider's chest, forcing him to push River away for his own safety. Before leaving, River takes a fake diamond from Spider's tie as a token or bargaining chip.

River races through the London Underground to Regent's Park Station, where he plans to infiltrate the embassy to access the vetting files. Upon arrival, he hands the fake diamond to Nick Duffy, a rival operative, to verify its authenticity. Duffy is suspicious and insists on accompanying River to the lab to confirm whether the diamond is genuine. To create a distraction and confusion, Jackson instructs Ho to call in a fake threat to the police, buying them some time.

While River and Duffy proceed to the lab, Diana Taverner, the deputy director-general of MI5, spots them inside the building. She confronts River privately, expressing her frustration and blaming him for her demotion to menial duties. She orders River to leave the building immediately, warning him that if she has to come looking for him, it will not end well. River complies but remains determined to complete his mission.

Meanwhile, River's mission becomes more complicated when Hobbs, another member of Slough House, insists on tagging along. River tries to shake him off, but the situation escalates until River knocks Hobbs down, though not unconscious, to continue his task alone.

Outside Slough House, Jackson notices a tail following him. He quickly realizes the tail is Shirley and Marcus, who are assigned to follow him. Jackson manages to evade them by getting picked up in a van, but Shirley and Marcus track the van's location through a ping on Cartright's phone, giving them a lead on Jackson's whereabouts.

Back at Regent's Park, River manages to locate the Prime Minister's vetting files in the embassy basement. However, as he attempts to escape with the files, he is confronted by Diana Taverner again, who tries to stop him from leaving. River narrowly escapes her grasp but is caught in a traffic accident shortly afterward, which causes him to lose the vetting files.

The episode ends with Catherine, who had been kidnapped, being reunited with the Slow Horses team. She is visibly traumatized by her ordeal. River promises to protect her and vows to seek revenge on Diana Taverner for her role in the events that transpired. The team begins to regroup and plan their next moves as the threat against them continues to loom.

At the end of Slow Horses Season 3, Episode 2, "Hard Lessons," River Cartwright fails to secure the Prime Minister's vetting files due to a traffic accident that causes him to lose the documents. Catherine Standish, who had been kidnapped, is reunited with the Slow Horses team but is visibly traumatized. Meanwhile, Jackson Lamb and the team lose track of a suspicious man who escapes in a van, leaving them without new leads. River vows to protect Catherine and seek revenge on Diana Taverner, who obstructed his mission.

The episode unfolds with River bolting out of Slough House and rushing to a bridge, where he receives a dire message from Spider (James Webb), who is being blackmailed. Spider pressures River to retrieve the Prime Minister's vetting files from Regent's Park by midday, threatening Spider's family's lives if he fails. River takes a fake diamond from Spider's tie as a token and races through the underground to Regent's Park Station.

At the Embassy, River hands the diamond to Duffy, who is suspicious of its authenticity. Duffy insists River accompany him to verify the diamond. To create confusion, Jackson has Ho call in a fake threat to the police. Meanwhile, River's mission becomes more complicated when Hobbs insists on accompanying him, doubting River's clearance. This leads to a confrontation where River knocks Hobbs down but does not incapacitate him.

Inside the archive room, River pleads with Molly, the archivist, to grant access to the Prime Minister's vetting files, explaining Catherine's life is at stake. Molly refuses, and River is forced to search forcefully but cannot locate the files. Time is running out, and River's mission is failing.

Simultaneously, Jackson Lamb informs Shirley and Marcus that they have been tailed outside Slough House. They attempt to follow a suspicious man but lose him when he is picked up by associates in a van. The agents are left without any new information.

The episode closes with River escaping a traffic accident but losing the vetting files in the process. Catherine is found and reunited with the Slow Horses, but she is deeply traumatized by her ordeal. River promises to protect her and vows revenge on Diana Taverner, who had obstructed his efforts. Jackson Lamb remains calm and sarcastic, continuing his own investigations quietly.

Fates of main characters at episode end:

• River Cartwright: Fails to retrieve the files, loses them in an accident, but remains determined to protect Catherine and seek revenge on Taverner.
• Catherine Standish: Rescued and reunited with the team but traumatized by her kidnapping.
• Jackson Lamb: Continues to lead the team, loses the tail on the suspicious man but pursues other leads.
• Shirley and Marcus: Fail to capture the suspicious man who escapes.
• Diana Taverner: Obstructs River's mission, becoming a target of River's animosity.

This detailed sequence highlights the escalating tension and the precariousness of the Slow Horses' situation, with key characters facing setbacks and unresolved threats as the episode ends.

The TV show Slow Horses, Season 3, Episode 2 titled "Hard Lessons" (2023), does not have a post-credit scene. None of the detailed episode recaps or reviews mention any scene occurring after the credits. The episode ends with the main plot developments around River's mission and the tense situation involving the Prime Minister's vetting files, but no additional post-credit content is described in the available sources.

River Cartwright is tasked with retrieving the Prime Minister's vetting files from Regent's Park under extreme time pressure, as failure would result in the death of Catherine, who has been kidnapped and is being used as leverage.

River races through the underground to Regent's Park Station and then to the Embassy to retrieve the files. He is given a fake diamond by Spider as part of the mission, which Duffy later discovers is counterfeit. River also has to deal with Hobbs tagging along, leading to a physical confrontation. Additionally, River is discovered by Diana Taverner, who tries to stop him, and he is later caught in a traffic accident, losing the files.

The fake diamond is used as a prop in River's mission to create confusion and facilitate the retrieval of the vetting files. Duffy decides to verify the diamond's authenticity, which adds tension and urgency to the mission when it is revealed to be fake.

Catherine is kidnapped and held hostage, with a photo of her being threatened sent to Slough House. Her kidnapping drives the urgency of River's mission and deeply affects the team, especially River, who promises to protect her and seeks revenge on those responsible.

Jackson quickly realizes he is being tailed and has Shirley and Marcus tail the suspect in return. They lose the tail when Jackson is picked up in a van, but they track the location through a ping on Cartright's phone. The team is actively working to uncover and counter the threats against them while managing internal tensions and external dangers.

The TV show Slow Horses, Season 3, Episode 2 ("Hard Lessons"), is not family friendly and is rated for mature audiences due to its content. It contains moderate to severe violence, including graphic and bloody scenes such as gunshot wounds and a severed head, which may be upsetting for children or sensitive viewers. There is also mild sexual content, including brief nudity and passionate kissing, as well as strong coarse language and references to alcohol and drugs. The episode features intense and frightening scenes typical of a spy thriller, which could be disturbing for younger or sensitive audiences.

Potentially objectionable or upsetting aspects include: - Graphic violence with blood and gunshot wounds - A severed head shown on screen - Mild sexual nudity and adult themes - Strong profanity and coarse language - Intense and suspenseful thriller elements

Given these factors, the episode is best suited for mature viewers and is not recommended for children or those sensitive to violence and adult content.