Lynda La Plante has confirmed she is writing a sequel to Prime Suspect which will be adapted for TV in 2016. The prequel, called Tennison, will flesh out the back story of La Plante's famous detective, played by Helen Mirren in the classic ITV series.

Helen MirrenHelen Mirren Was Already A Star When She Joined 'Prime Suspect'

"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," La Plante told This Morning on Tuesday.

"But nobody knows what drove her to become a DCI [detective chief inspector] or want to join the police force in the first place. When you first meet her in the early 1990s, 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."

Mirren was already a star when she appeared in the ITV show, which ran for seven series from 1991 to 2006. 

La Plante is now on the hunt for a new star to play the young detective though concedes it will be a difficult job to find an actress with the some on-screen intensity as Mirren.

"Her depth as an actress is astonishing. It was wonderful to watch her really bring that character to life."

Prime Suspect was voted 68th in a British Film Institute poll of the 100 greatest British TV programmes.