Line of Duty nicks top spot as 4 million watch finale

Detective Sergeant Steve Arnott played by Martin Compston and Vicky McClure as Detective Constable Kate Fleming in BBC2’s Line of Duty. Photograph: Mark Bourdillon/BBC/World Productions

BBC2’s explosive Line of Duty finale was watched by more than 4 million viewers – beating BBC1 and ITV on Thursday night.

The 90-minute climax to Jed Mercurio’s acclaimed police corruption thriller had 4.1 million viewers, a 20.6% share of the audience from 9pm last night.

Related: Line of Duty review – an intense, butt-clenchingly brilliant finale

It beat BBC1’s rural extravaganza Secret Britain, which had 2.5 million viewers (12%), also from 9pm, and ITV’s Emma Willis modern medicine show What Would Be Your Miracle?, which began with just 1.8 million viewers, an 8.5% share.

Line of Duty, which has already been commissioned for a fourth series, is BBC2’s biggest rating drama since modern ratings methodology began in 2002, beating last year’s Wolf Hall.