Lynda La Plante is writing a prequel to Prime Suspect which she will adapt for TV in 2016, the 25th anniversary of the hit ITV drama. The prequel will be called Tennison, after its main character, Jane Tennison, and was revealed by La Plante on Tuesday as she launched a new company, La Plante Global, incorporating all of her print and screen interests.

“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.”

La Plante did not identify which broadcaster would screen the prequel, or even if it had been commissioned, but its natural home would be ITV where Prime Suspect ran for seven series, spanning 15 episodes, from 1991 to 2006. It was also adapted for US TV.

Mirren was already a star when she appeared in the first episode, but the Bafta-winning drama made her a household name. La Plante said: “At an event, a big book signing, a fan came up to me and she said ‘Where did Tennison get that aloof coldness from? What did she do when she was young?’

“It sat in my head so I am coming out with Tennison, back in the 1970s and 1980s, how she became a DCI?”

La Plante said she could not wait to begin the casting search for a new star to play the young detective. She said of Mirren: “Her depth as an actress is astonishing. It was wonderful to watch her really bring that character to life.”

La Plante Global will control all of the author’s future book, TV and film deals. Prime Suspect was voted 68th in a British Film Institute poll of the 100 greatest British TV programmes.

John Plunkett – theguardian.com, Wednesday 19 February 2014