DS Steve Arnott is transferred to the police anti-corruption unit after the death of a man in a mistaken shooting during a counter-terrorist...

An ambush of a police convoy results in three police officers dead and a protected witness seriously injured. The sole surviving police officer is...

After a criminal is shot dead during a police raid, the AC-12 team begins examining the conduct of Sergeant Danny Waldron, leader of an elite unit....

The fourth series sees AC-12 facing their most devious opponent yet! Under pressure from her superiors, DCI Roz Huntley charges a young man with a...

Series 5 follows the actions of Superintendent Ted Hastings, D.I. Kate Fleming and D.S. Steve Arnott as they investigate an Organised Crime Group...

Series 6 sees AC-12 facing their most enigmatic adversary so far: Detective Chief Inspector Joanne Davidson, the senior investigating officer of a...

DCI Roz Huntley is under intense pressure from her superiors to apprehend a serial murderer after months of fruitless investigation.

AC-12 crank up their investigation into Operation Trapdoor. Kate makes progress in her undercover role.

As AC-12 wrestle with the new forensic evidence casting doubt over Tim Ifield, Kate is approached by another woman claiming to have been assaulted by...

Roz's husband Nick is brought in for questioning by AC-12. But while Nick denies any involvement in Steve's attack, his suspicions about Roz mount.

DCI Roz Huntley struggles to allay her husband's suspicions. AC-12 find a new angle to pursue their case against her.

While Nick Huntley faces lengthy questioning, AC-12 remain convinced of Roz's involvement.