But I thought, 'Go with the flow', what could you do, to be honest.' They didn't do it to the men, just the women. 'They did it to me twice, it was humiliating. 'It was a very common occurrence getting your backside stamped,' says Jackie. One of the rituals for women was to have their pants pulled down and a CID ink stamp on their buttocks. She quickly rose through the ranks and in 1973, at just 22, she became a sergeant joining CID. 'The men got a baton instead of a handbag.' 'You couldn't get anything into it, mind,' says Jackie. In 1970, aged 19, Jackie joined Leicestershire Police, where women were given a whistle, handcuffs and a handbag. It is an incredible memoir of one woman's determination to be an officer in a time when policing was more like The Sweeney or Life On Mars. In her new book - The Real Prime Suspect - Jackie, who is gay, reveals how she fought against sexism and homophobia to carve out a hugely successful career. It was a massive moment in Jackie's life too, who at the time was one of just three female DCIs in the Metropolitan Police.

That story went on to be a massive success, with 14 million viewers in the UK, selling to 78 countries, a global audience of 200 million and a major career moment for Helen Mirren. 'It was 1991 and I thought the audience wouldn't be ready for it - it would distract from the story.' 'When Lynda said perhaps we should make her gay, I said no,' says Jackie. Together they created one of the most iconic TV characters of the past 30 years and set the bar for small screen police drama.

Prime Suspect by Lynda La Plante