LINE OF DUTY: SERIES FINALE TRAILER RELEASED

The final episode of the series airs this weekend, following record breaking viewing figures.

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.

Line Of Duty concludes this Sunday at 9pm on BBC One.