Line of Duty

When three police officers are shot dead during the hijacking of a seized-drugs transport, AC-12 moves in to investigate possible police collusion.

DI Kate Fleming and DS Steve Arnott attempt to track down the undercover officer embedded in an organized crime group. A fresh police leak enables another audacious raid, while Steve’s attempts to make contact with the undercover officer put him in the sights of its violent leader.

Corbett’s most audacious plan yet requires McQueen to exploit links with corrupt police officers. AC-12’s shocking discovery about one of their own reveals the scale of the corruption, including the enigmatic figure known only as “H.”

Tensions mount between Corbett and McQueen in the fallout from the Eastfield raid. A breakthrough by AC-12 creates an opportunity to capture Corbett. With troubling questions hanging over the identity of “H,” Hastings’s erratic conduct makes Kate and Steve wonder about his motives.

Kate and Steve investigate Corbett’s past and uncover evidence that may explain Hastings’s increasingly reckless behavior. Meanwhile, the hunt for “H” intensifies.

Carmichael’s dogged interrogation of Hastings presents mounting evidence of suspicious behavior. Caught in the crossfire, Kate and Steve are torn between loyalty to Hastings and their duty to uncover the truth, however painful. Will the identity of “H” be revealed at last?