Catherine Standish is a British intelligence administrator and a key character in the series Slow Horses. She works at Slough House, a department for disgraced MI5 agents, under the leadership of Jackson Lamb. Portrayed by Saskia Reeves, Catherine brings a quiet strength and determination to her role, despite being haunted by a tragic past involving her former boss, Charles Partner. Her character navigates the challenges of the intelligence world while seeking redemption and closure, making her a central and complex figure in the series.

Trivia/Facts

• Catherine Standish is a British intelligence administrator. She currently works at Slough House. Her character is portrayed by Saskia Reeves. Catherine appears in all four seasons of Slow Horses.
• Before joining Slough House, Catherine was a secretary and personal assistant. She worked for Charles Partner, the former Director-General of MI5. They developed a close relationship, and he helped her with her alcoholism. This support was significant in her life.
• One day, Catherine found Charles dead in his bathtub. It appeared to be a suicide by self-inflicted gunshot. However, it was later revealed that Jackson Lamb actually killed him. Catherine was unaware of Lamb’s involvement.
• Charles’ death left a lasting impact on Catherine. She was haunted by the incident for many years. Eventually, she was assigned to Slough House without knowing Lamb was responsible for her mentor’s death. She also faced a near-charge of treason related to Partner’s activities.
• Catherine is portrayed as a talented chess and Scrabble player. These skills show her intelligence and strategic thinking. Her identification number in the service is Officer Ref: GD/0549. This reflects her position within the intelligence community.

Saskia Reeves in Slow Horses (2024)

• Catherine often interacts with Jackson Lamb, who has a blunt demeanor. In one scene, he calls her to his office, expressing his frustration with MI5. Despite Lamb’s tough exterior, Catherine remains professional and focused on her work. Their relationship is complicated due to their past.
• Catherine participates in group therapy sessions, where she has flashbacks about Charles’ death. These moments highlight her emotional struggles. She also encourages other agents like River when they are feeling down. Her supportive nature contrasts with the harsh environment at Slough House.
• Catherine navigates various challenges at Slough House, often under Lamb’s direction. She balances her duties while dealing with the aftermath of Charles’ death. She shows determination to contribute, even in a difficult environment. Her role often requires her to manage chaotic situations.
• Throughout the series, Catherine plays a crucial role in various missions. She assists her colleagues in gathering information and tracking suspects. Her insights and skills are valuable assets to the team. Despite the team’s dysfunction, she remains committed to their objectives.
• Catherine has a tense relationship with Diana Taverner, a senior MI5 official. She demands answers regarding Partner’s death, showing her determination for justice. This confrontation highlights her resilience and refusal to back down. Catherine’s quest for truth adds depth to her character.
• By the end of the series, Catherine’s character evolves significantly. She grapples with her past while trying to forge a new path. Her strength and loyalty to her colleagues shine through. Catherine Standish remains a complex and compelling figure in Slow Horses.

Catherine Standish’s Relationship with Other Characters

• Jackson Lamb: Catherine works closely with Jackson Lamb, her boss at Slough House. Jackson is rough and often rude, but Catherine stays calm and professional. She doesn’t know that Jackson is secretly connected to the death of her old boss, Charles Partner. Despite Jackson’s tough behavior, Catherine continues to follow his orders and do her job well.
• Charles Partner: Catherine was the secretary and personal assistant to Charles Partner, the former head of MI5. She had a close bond with him because he helped her overcome alcoholism. His sudden death shocked and deeply affected her. She doesn’t know that Jackson Lamb was the one who caused Charles’ death, believing it was a suicide.

Saskia Reeves in Slow Horses (2024)

• River Cartwright: Catherine interacts with River, a younger agent at Slough House. She often offers him advice and tries to support him, especially when he’s frustrated or upset. River respects her experience and listens to her when he needs guidance. They share a professional but caring relationship.
• Diana Taverner: Catherine has a tense relationship with Diana Taverner, a high-ranking MI5 official. Catherine wants answers about her old boss, Charles, but Diana refuses to give her the full truth. This creates distrust between them. Catherine is determined to find out what really happened, making their relationship complicated.