DI Kate Fleming is AC-12's secret weapon: a gifted undercover specialist who can embed herself inside a suspect's team and earn their trust while quietly gathering the evidence to destroy them. Cool under pressure and ferociously observant, she pays for her talent with a fractured home life, sacrificing her marriage and time with her son to live a lie for the job.
Her loyalties are tested again and again as the people she infiltrates become colleagues, friends, and sometimes something closer. The strain of perpetual deception leaves her isolated, and a growing rift with Steve over trust and tactics fractures the partnership that once defined the unit.
In the later series Kate makes the painful decision to leave AC-12, only to be pulled back into the orbit of the conspiracy through a charged, dangerous relationship with DI Jo Davidson. Her instincts as a reader of people prove decisive in the endgame, and her bond with Steve, battered but unbroken, endures.
Key Episodes
S1 E1
Episode 1
Kate goes deep undercover inside Tony Gates's team, charming her way into his confidence as AC-12 begins building its case against the celebrated officer.
S6 E7
Finale
Kate's read on Jo Davidson and her unflinching work in the interview room help corner the conspiracy, even as the unmasking of H lands with a grimly ordinary thud.
Kate Fleming 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, Kate Fleming 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 Vicky McClure, Kate Fleming has become one of the most recognizable characters in modern television. Vicky McClure's performance brings nuance and depth to the role, creating a character that resonates with audiences on both intellectual and emotional levels. Vicky McClure's work has been recognized with 1 major award, reflecting the critical acclaim their portrayal has received.
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? Frequently Asked Questions
Vicky McClure plays DI Kate Fleming in Line of Duty.
Kate Fleming is AC-12's most skilled undercover officer, able to infiltrate suspect teams and gain their trust while secretly gathering evidence. Brilliant at reading people but worn down by years of living a lie, she sacrifices her family life for the job and forms a fierce, enduring partnership with Steve Arnott.
