Line of Duty

DCI Jo Davidson faces increasing pressure from all sides as AC-12 make major breakthroughs in the investigation.

Hastings acknowledges that the disciplinary action against him put Kate and Steve in a difficult position, and a forensic report from Farida's house results in a shock for AC-12.

AC-12 link Gail Vella's murder with a historic case of police corruption, and Kate hatches a plan to tell once and for all if Jo is bent.

They are closer than ever to cracking the case, but when Hastings' authority is undermined it leaves his team in a potentially dangerous situation.

As AC-12 struggle to deal with the repercussions of tragic events, Hastings makes one final bid to uncover institutionalised corruption before his time runs out.

With time running out, AC-12 attempt to unmask 'H', the Fourth Man (or Woman) commanding the network of corrupt officers behind the murder of Gail Vella. But sinister and powerful forces appear intent on orchestrating a cover-up.