Line of Duty is a British BBC police procedural television series created by Jed Mercurio. The first series premiered on 26 June 2012 and became BBC Two's best-performing drama series in 10 years with a consolidated audience of 4.1 million viewers. The drama was recommissioned for a second series and the first episode was broadcast on 12 February 2014. The second series achieved widespread public and critical acclaim and on 8 April 2014, the BBC commissioned a further two series back to back. The third series broadcast began on 24 March 2016, and the fourth on 26 March 2017 on BBC One. Filming of the fifth series is complete for broadcast in the UK in 2019. The BBC has ordered a sixth series.
It is the most popular drama series broadcast on BBC Two in the multi-channel era and is a winner of the Royal Television Society Award and Broadcasting Press Guild Award for Best Drama Series. Line of Duty was included in a list of the Top 50 BBC Two shows of all-time and in a list of the 80 best BBC shows of all time. It was the highest-ranked current series in a list of the best cop shows of all time and in a poll of the best British crime dramas of all time.