She said: “No one could foresee the success Bodyguard, but the moment I saw the script for The Capture I knew it had that certain something. It’s a production I would definitely want to watch.”To prepare for the role, she shadowed a young female homicide detective for a week.Ms Grainger will star alongside Callum Turner, who recently appeared in War & Peace and is playing soldier Shaun Emery.The storyline follows the troubles faced by Mr Emery, whose conviction for murder while serving in Afghanistan is overturned due to flawed video evidence.However, his freedom is bried – shortly after he returns to life with his young daughter, damning CCTV footage from a night out in London surfaces and Shaun’s life begins to unravel, forcing him to fight for his freedom once again.D.I Rachel Carey is on his case, and the series follows her discovering the truth. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. The lead actress in the BBC’s new police thriller – billed as the “new Bodyguard” – said she only agreed to do a sex scene in the opening episode because the director asked for her opinion first.Holliday Grainger is set to take the main role in “The Capture”, a six-part surveillance thriller which begins next month.The show will tell the story of an innocent man falsely accused in the ‘post-truth’ era.Ms Grainger, who has chiefly appeared in period dramas, told the Mail on Sunday: “There’s a bedroom scene at the beginning of The Capture, and part of me was thinking, ‘Oh here we go, are we really going to introduce my female character with a sex scene?’ “I’d normally put my foot down and say, ‘I’m not getting naked in the first episode.’ But the fact that Ben [Chanan, writer-director] wanted my opinion is a sign of positive change.”It’s significant that he came to me and said, ‘Is it too much?’ Pre-#MeToo we might not have even been having that conversation.”The 31-year-old, who is playing Detective Inspector Rachel Carey, thinks the show will be as gripping as “Bodyguard”, the popular BBC show which fascinated the nation last year.