DS Steve Arnott arrives at AC-12 as an idealist with a chip on his shoulder, having transferred to anti-corruption after refusing to cover up a botched counter-terrorism raid that left an innocent man dead. Sharp-suited and stubbornly principled, he becomes the unit's relentless interrogator, the man who keeps pulling threads even when every instinct tells him to stop.
Over the years the job grinds him down in body and spirit. A near-fatal fall down a stairwell leaves him with chronic back pain and a quiet dependence on painkillers, a vulnerability he hides behind professional bravado. His tangled personal life and a string of compromised relationships repeatedly blur the line between his work and his judgement.
By the final series Steve is exhausted, disillusioned, and increasingly at odds with a Ted Hastings he can no longer fully trust. Yet his commitment to the truth never quite breaks, and it is his bulldog persistence in the interview room that helps drag the conspiracy's last secrets into the light.
Key Episodes
S1 E1
Episode 1
Steve refuses to fall in line over a deadly armed-raid cover-up, is frozen out by his colleagues, and is recruited into AC-12, setting his anti-corruption crusade in motion.
S6 E7
Finale
A weary, pill-dependent Steve presses through the climactic interrogation that finally exposes the identity of the elusive fourth man, even as the result lands as a deflating anticlimax.
Steve Arnott is one of the central figures in Line of Duty, a crime/drama/thriller series that aired on BBC One from 2012-2021. Within the narrative of Line of Duty, Steve Arnott serves as a pivotal character whose decisions and relationships drive key story arcs throughout Seasons 1-6. The character's journey has been central to many of the show's most memorable and discussed moments.
Portrayed by Martin Compston, Steve Arnott has become one of the most recognizable characters in modern television. Martin Compston's performance brings nuance and depth to the role, creating a character that resonates with audiences on both intellectual and emotional levels. Martin Compston's work has been recognized with 1 major award, reflecting the critical acclaim their portrayal has received.
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? Frequently Asked Questions
Martin Compston plays DS Steve Arnott in Line of Duty.
Steve Arnott is a principled detective sergeant in AC-12 who joins the anti-corruption unit after refusing to cover up a fatal police raid. Known for his sharp suits and dogged interrogation style, he spends the series chasing bent officers while battling chronic pain, painkiller dependence, and a messy personal life.
