Speaking to This Morning, La Plante said she wanted to explore the early life of tough-talking character Jane Tennison - made famous onscreen by Dame Helen Mirren.She also reveals plans to adapt the book, called Tennison, for TV.La Plante said: "I am extremely excited to have begun work on the Tennison project."Jane Tennison is a character who millions of people know and admire from my books and TV series, Prime Suspect, portrayed brilliantly by Helen Mirren."But nobody knows what drove her to become a DCI or want to join the police force in the first place. When you first meet her in the early 90s, she is a very complex character, but what made her so?"I can't say too much now, but readers will find out next year when the book is published; or in 2016, which is the 25th anniversary of Prime Suspect, when they watch Tennison the series."