Line of Duty is a British BBC police procedural television series created by Jed Mercurio. It was BBC Two's best-performing drama series in ten years with an audience of 4.1 million viewers. A second season was ordered. Its success led to the BBC ordering a further two series. The third series broadcast began on 24 March 2016, and the fourth on 26 March 2017 on BBC One. The fifth series was completed at the end of 2018. It was broadcast on BBC One on 31 March 2019. The BBC has ordered a sixth series.