The series opener of police drama Line Of Duty failed to topple ITV’s detective series Vera in the Sunday night ratings battle.

Despite a record audience tuning in to watch newcomer DCI Roz Huntley, played by Thandie Newton, on the hunt for a serial killer, the hour-long episode fell short of Vera’s viewing figures as it kicked off its fourth series.

Vera, starring Brenda Blethyn in the titular role, returned last week for its seventh series. Despite losing 1.2 million viewers in the seven days since the opener, the two-hour show won the 8pm to 10pm timeslot with an average audience of 5.2 million.

That meant an overall share of 24%, according to ITV’s overnight ratings which includes viewers who watched the drama unfold on the ITV+1 channel.

Meanwhile on BBC One, Line Of Duty, which peaked at 5.2 million, averaged five million viewers with 23% of the overall share from 9pm to 10pm, according to BBC overnight ratings.

It marks a triumphant return for the drama with a rise of almost two million in audience figures, compared with the launch of the third series last year.

However, fans were left concerned by the episode’s climax as Thandie’s Roz appeared to have been killed in a struggle with forensics co-ordinator Tim Ifield (Jason Watkins).

The pair scuffled during a row and Huntley hits her head and collapses. But as Ifield powers up a chainsaw and prepares to dispose of the body, Huntley flicks open her eyes.