A record 12.8 million viewers tuned in for the final episode of series six of the hit BBC One drama Line of Duty when it aired on Sunday night. Commanding 56.2% of the UK’s television audience, according to overnight figures, the BBC said it was the most watched episode of any drama, excluding soaps, since modern records began in 2002. With viewers tuning in to find out the identity of the show’s enigmatic criminal mastermind, H, the five-minute peak audience was 13.1 million between 9.45pm and 9.50pm, the end and aftermath of the interrogation of the “fourth man”. The last time a TV drama reached higher viewer figures was for an episode of ITV’s Heartbeat in 2001, which attracted an overnight audience of 13.2 million. Though overnight viewing figures do not count for as much as they once did, given significant changes in viewer habits, particularly with the rise of streaming and on-demand services, Line of Duty’s viewers have defied the trend and continued watching live, keen to follow the latest plot twists and avoid spoilers on social media. Sunday’s much-anticipated instalment drew in close to 4 million more viewers than the last series’ finale, which was watched by 9.07 million in 2019. Created by the British writer Jed Mercurio, Line of Duty first aired in 2012. Following the investigations of police anti-corruption unit AC-12, it has become one of the highest rated British dramas ever. But with six series wrapped and many questions left unanswered, audiences have been left wondering if it will return for a seventh. Ahead of the finale’s broadcast, Mercurio thanked the BBC for “six incredible seasons” and paid tribute to the cast and crew. But in a statement the BBC hinted it would be open to Mercurio making more. Charlotte Moore, the corporation’s chief content officer, said: “Addictive event television, Line of Duty has kept the nation guessing for the last seven weeks, so it’s no surprise that last night’s jaw-dropping finale set a ratings record. “Jed Mercurio is a master of his craft, and I would like to congratulate him and the entire cast and crew for delivering such an incredible drama series. I’m looking forward to having a conversation with the team about where we go next and what the future of the series might be.” Despite the high viewing figures, the finale of series six provoked mixed responses, with “disappointing” trending alongside Line of Duty on Twitter on Sunday night. The Guardian’s Lucy Mangan gave it three stars, citing plot holes throughout the season and the loss of key elements that made the show great, including the connection between Kate and Steve. Series six “superficially at least, delivered”, she said of the big reveal of the identity of H, but she suspected it was “anticlimactic” for many fans and the many cliffhangers would leave them, like her, wanting more. “It was all fine,” she wrote. “But, oh my, you should have seen it when it was good.”