A determined agent at Slough House, driven by a desire to redeem himself after a major error during a training exercise.

The composed and disciplined administrator at Slough House, maintaining order amidst chaos while managing her recovery from alcoholism.

A high-ranking MI5 official known for her ruthless ambition and strategic manipulation within the intelligence community.

An efficient and withdrawn operative at Slough House, coping with personal loss while remaining professionally competent.

A former army colonel with a personal vendetta, using his military skills to navigate a complex and dangerous situation.

A disgraced tactical agent at Slough House, struggling with a gambling addiction and longing for his past active role.

A fiery and troubled agent at Slough House, dealing with anger issues and substance abuse while showing sharp instincts.

The tech-savvy and socially awkward hacker at Slough House, providing digital expertise crucial to the team's operations.

The ambitious home secretary, leveraging his political position for personal gain while masking his true intentions.

The head of MI5, maintaining control through political maneuvering and prioritizing her authority within the institution.

A private security firm leader involved in a risky operation, ultimately served by his overconfidence and misplaced trust.

The head of MI5’s internal security, known for his authoritative approach and role as the enforcer within the Service.