One time Senior Investigating Officer and retired detective superintendent Bob Bridgestock and Carol Bridgestock have harnessed their 45 years police service to write Deadly Focus.

The book, set in the imaginary town of Harrowfield, centres on the hunt for a young girl called Daisy Charlotte Hind who vanishes without a trace as she goes to show her grandmother her bridesmaid's dress.

How autobiographical the experience of lead character SIO Jack Dylan is, as he confonts his worst nightmare when Daisy's body is discovered and another child goes missing, is not clear.

But the knowledge of how serial killer investigations are carried out and how they affect the principle characters has the ring of authenticity.

Dylan is attacked on the job and finds his health under increasing strain as he struggles to find a balance between his passion for his job and love for his partner Jen. Will he be able to catch the killer and secure justice for the victim's families?

Tingley and Birstall-raised Bob, 57, retired to the Isle of Wight with Carol five years ago after 30 years service, all but two as a detective.

The ex-Morley Grammar School pupil had worked on the horrific abduction murder of Morley schoolgirl Sarah Harper and later headed many high profile cases including the house fire in Birkby, Huddersfield in 2002 which killed eight members of one family. He was also a skilled hostage situation negotiator, successfully diffusing deadly situations.

"My police service was an incredible experience, which helped me to prepare for most things that life throws at you. In every walk of life, it's the people who make the workplace an enjoyable environment and Carol and I both miss the banter and our friends," he said.

But he recalled, "A previous SIO once told me that three years in the role was saturation point and after five I knew he was right. In my final three I dealt with 26 murders and 23 major incidents including shootings and attempted murders, plus more than 50 suspicious deaths – many in Leeds – and numerous serious sexual assaults. So the truth is it was time to go before my whole being was taken over."

"The smell of the mortuary has now cleared from my nostrils and I have found the freedom that retirement offers – no pagers or phones to disturb our sleep or incidents dictating days off," he said.

After cajoling from friends and family who enjoyed the police anecdotes, the couple made a life changing decision and enroled on a Write Your First Novel course.

Bob managed to turn out 120,000 words in six weeks – in longhand – in his own conversational style of writing.

Bob explained: "Deadly Focus is a detective novel and we cannot deny we have drawn on our extensive knowledge of police work."

Carol said: "You've probably heard the saying, 'there's a book in everyone' and for years, Bob has had people both laughing and crying with all the tales he has told. But whenever anybody said he should write a novel, he always said no, so you can imagine my surprise when he enroled us on the writing course."

Now they work as co-authors under the name R C Bridgestock.

" We thought it added to the conspiracy by making it look like it was one author. Bob writes the structure of the story and I write the emotional side of it and 'craft' his work for him. It works really well for us and we have both really enjoyed writing Deadly Focus"

Carol said: "Our family and friends have all been involved over the past year or so and they are all intrigued by the book. But very few people have read the finished piece and we want to keep it that way until it hits the shops. It all adds to the mystery."

The couple have just finished their second novel Consequences and have already started a third.

Talking of his move down south after retiring, Bob said, "We were asked 'Why the Isle of Wight?' Carol once took me to visit her childhood home on the south coast from where, across the Solent, I saw the Isle of Wight. Sitting on the spit head at Hurst Castle she told me of her young childhood dreams about the island and we decided to visit."

"Neither of us have any doubts it is the place for us. Lovely countryside, nearby beaches, fresh air – the list is endless. The pace of life is idyllic and crime is low – utopia for a retired policeman."

"We kept very busy for the first couple of years by renovating our home plus walking our golden retriever along the beaches and through the woods. We also bought a springer spaniel and she had five pups. It took a while to realise that this was now our life. We felt very lucky.

As well as their writing, Bob and Carol have also produced and presented Carisbrooke Castle – a factual docu-drama taking you through 1000 years of a local landmark.

Having been shown on Sky television in April 2009 the production is now being used as a tourism guide for the Isle of Wight. The team are now also in talks with the local Department for Education for it to be used as a visual aid tool in schools and with English Heritage for potential inclusion in their outlets.

"We consider ourselves to be very fortunate," Carol said.

Deadly Focus will be available through Waterstones and online bookstores, including Amazon.