A tale of passion, deception and intrigue set in London and Thailand against a backdrop of the dangerous world of international drug smuggling may seem like the stuff of thrillers.

It is... but it was also the world of author Frank Hurst, who worked in international drugs intelligence for more than 35 years and has just published his debut novel inspired by his career.

Frank, who lives in West Chiltington, began writing The Postmistress of Nong Khai when he retired in 2011. “All the time I was actually doing my job, I kept thinking, ‘There’s a novel in this somewhere’,” says Frank. “But I didn’t have the energy to do anything about it until I retired.”

His debut novel, which is set in the 1980s, tells the story of intelligence officer Mike Rawlin, who falls for his beautiful Thai informant, setting him on a path that could wreck both his investigation and destroy his life. An ambitious Customs intelligence officer based at the British Embassy in Bangkok, he’s charged with the task of infiltrating a dangerous band of drug smugglers. With the help of his beautiful informant Lek, he closes in on the capture of Dutch drug lord Bart Vanderpool.

As he embarks on a passionate affair with Lek, his personal and professional values begin to disintegrate and he has to choose between his love for Lek and his desire to bring down the man he has been hunting for 10 years.

It’s a world Frank knows intimately. He was recruited in the 1970s when he joined the civil service on his father’s advice after failing to get a degree at university. “I was a lazy chap then,” laughs Frank. He worked with Her Majesty’s Customs, Scotland Yard and the British Foreign Office tracking down drug smugglers, interviewing suspects and accompanying detained suspects.

“In the 1970s and 1980s, the drugs problem was dealt with from the London office,” explains Frank. “But of course all drugs came from abroad and they had worked out by the mid-1980s that if there were offices abroad, we could steal a march on the drug smugglers via the intelligence angle.

“I started doing a lot of work in the Thailand office, then spent five years in India and six years in the East Caribbean. I realised I was involved in an interesting job and knew there was a book in it somewhere.”

In 1988, Frank was part of the international operation that arrested and convicted Howard Marks and his associates. Marks, described by the press as “the most sophisticated drugs baron of all time”, was busted by the American Drug Enforcement Agency and sentenced to 25 years, then released on parole in 1995. He was “the enemy” as far as Frank was concerned but he still had a certain amount of admiration for him.

“He ran rings around us for a year,” recalls Frank. “His lifestyle to me as a young officer was very glamorous and he never dabbled in hard drugs.”

Frank now divides his time between West Sussex, where his daughter and grandson live, and Phuket in Thailand. He has begun writing his second novel, a sequel to The Postmistress of Nong Khai.

“Writing is much harder than my job was,” he says. “The job was a lot of fun and I would do exactly the same job if I had my time over again, but to write I need a lot of peace and quiet. Luckily, I have been able to get that.”

• The Postmistress of Nong Khai by Frank Hurst is out now, published by Matador and available on Amazon priced £9.99.