The BBC has revealed a dramatic teaser of the series finale of Line Of Duty.
Series 6 of the hit drama concludes this Sunday night at 9PM on BBC One.
A teaser for the final episode reads: "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."
You can watch the trailer below...
The teaser clip follows last night's latest episode reaching record ratings.
The the penultimate episode of series six hit an overnight audience of 11 million viewers, its highest ever rating.
Creator Jed Mercurio said on Twitter: "Thanks so much to everyone watching #LineOfDuty6. The whole production team is thrilled and flattered by the amazing response."
You can catch up on series 6 of Line Of Duty online and watch the past five series online via BBC iPlayer here.
Series 6 of Line Of Duty features a brand new case for AC-12, this time investigating DCI Joanne Davidson (Kelly Macdonald), the senior investigating officer on an unsolved murder case.
Returning to the cast Martin Compston, Adrian Dunbar and Vicky McClure will all return as DS Steve Arnott, Supt. Ted Hastings and DI Kate Fleming respectively.
Newcomers for the new season are Shalom Brune-Franklin as DC Chloe Bishop, Perry Fitzpatrick, Andi Osho and Prasanna Puwanarajah.
Writer Jed Mercurio said of series 6: "As with every series of Line of Duty, we introduce a brand new character. This series we have Kelly Macdonald who plays DCI Joanne Davidson. It’s a great device for allowing the series to be accessible to brand new viewers who have no knowledge of previous series.
"This series, AC-12 will investigate what’s going on at Hillside Lane Police Station in a case led by DCI Joanne Davidson and we look at the investigation of a cold case.
It’s a high profile murder case of Gail Vella that has remained unsolved for over a year and which the police force is struggling to solve. There’s been no closure."