A brutal ambush on a police convoy leaves three officers dead and a protected witness fighting for his life. AC-12 turns its spotlight on Lindsay Denton, the officer who led the convoy but escaped unscathed.
Steve Arnott is a young officer who's fallen foul of his superiors for refusing to help in the cover-up of an operation that ended in the shooting of an innocent father. He seems ideal to join AC-12, an anti-corruption police unit, just as it starts to investigate Detective Chief Inspector Tony Gates, the regional force's Officer of the Year.
Line of Duty - Series 2, Episode 1 Synopsis and Schedule