Line of Duty

“Line of Duty” (2012–2021): A Masterclass in Police Drama and Moral Complexity

Line of Duty, which aired from 2012 to 2021, stands as one of the most gripping and intelligent police dramas of the 21st century. Created by Jed Mercurio, the British series captivated audiences over six seasons with its unflinching portrayal of police corruption, complex storytelling, and morally ambiguous characters. From its humble beginnings on BBC Two to becoming a cultural phenomenon on BBC One, Line of Duty redefined the modern crime thriller.

At its core, Line of Duty follows the work of AC-12, a fictional anti-corruption unit within the police force, tasked with investigating officers suspected of misconduct. Led by Superintendent Ted Hastings (played by Adrian Dunbar), and supported by Detective Sergeant Steve Arnott (Martin Compston) and Detective Inspector Kate Fleming (Vicky McClure), the unit operates in a world where justice is murky and the truth is never straightforward. Each season focuses on a different suspect within the force, gradually revealing a wider network of organized corruption linked to the enigmatic figure known only as "H."

What made Line of Duty unique was its commitment to realism and moral complexity. The show didn’t rely on flashy action sequences or simplified good-versus-evil narratives. Instead, it built tension through long interview scenes, intricate investigations, and unpredictable twists. The dialogue, particularly during the lengthy interrogation scenes, was dense, intelligent, and often emotionally charged—challenging viewers to keep up with every subtle detail. Mercurio’s writing emphasized systemic flaws within law enforcement, exploring how power can be abused, covered up, and excused in the name of order.

Each season introduced a new character at the heart of AC-12’s investigation. Performances by Lennie James (as DCI Tony Gates), Keeley Hawes (as DI Lindsay Denton), Thandiwe Newton (as DCI Roz Huntley), and Stephen Graham (as DS John Corbett) were universally praised, offering layered portrayals of individuals trapped between duty and self-preservation. These characters weren’t outright villains—they were flawed humans making impossible decisions, often caught in the crossfire of larger conspiracies.

Adrian Dunbar’s portrayal of Ted Hastings became iconic, with his old-school charm, unwavering integrity, and memorable catchphrases (“Mother of God!”) making him a fan favorite. Meanwhile, the dynamic between Arnott and Fleming gave the show emotional grounding, as the two investigators struggled with loyalty, betrayal, and personal trauma throughout the series.

The final season, which aired in 2021, polarized some fans with its subdued reveal of “H,” the mysterious figure orchestrating much of the show’s corruption. However, others praised its realistic conclusion, staying true to the show’s core message: that institutional corruption is rarely the work of a single mastermind, but rather the result of systemic failure and complicity.

In retrospect, Line of Duty was not just a crime drama—it was a commentary on accountability, justice, and the fallibility of institutions. It proved that television could be thrilling without sacrificing intelligence or nuance. Even after its conclusion, the series continues to spark discussion, analysis, and admiration. Line of Duty remains a benchmark for British television, and its legacy will endure as one of the most compelling and thought-provoking police dramas ever created.