Devon-based author Peter Johnson appears to be the epitome of the retired schoolmaster.

Urbane and courteous, he describes his 17 years serving as the head of two schools (Wrekin College and Millfield School in Somerset) as some of the best in his life.

“The thing I miss most about not working is young people. I spent every day of my life with them and miss the fun of being around people who are so bright, buzzy and full of energy.”

Life changing experiences like retirement, which often force people to reassess their lives, are very much a central theme in his books.

His first novel published last year, ‘It’s Cold At The End Of The Bed’, is about a young man whose career as a rugby player is disrupted by injury. But his second work, ‘Plot One’ (Troubador Publishing), a family drama published a fortnight ago, is much closer to home and explores the problems faced by the leading character, John Stevens, who is a top headmaster having to readjust to retirement.

“The conversion to retirement is not always easy,” he admits. “It was something I needed to do but I had to convert to a different way of life, and that’s at the heart of the story. Your relationships within a family are some of the most powerful things to write about.”

They say write about what you know. Was he mirroring his own life?

“Stevens’ whole life has been devoted to that job (of headmaster) – I will admit that I was hugely committed to my work. But the book is also about his son and daughter who are in their 20s and his relationship with the family.”

Stevens is a ‘workaholic’; a word Johnson, who turns 76 this week, also uses to describe himself, but its the father-daughter relationship in ‘Plot One’ that has a particular resonance. When Johnson was in his 20s, his newborn son was diagnosed with spina bifida, a debilitating disease that forced Johnson to make a life-changing decision, because at the time he was serving in the army.

Prior to his son’t birth, he served two tours of duty in Northern Ireland in the early 1970s, during the height of the Troubles. Listening to Johnson it’s clear that resilience is very much part of his armoury. His gentle tone doesn’t change, even when recounting the sort of events that would shake most people to their core.

One of these involved the deaths of two army colleagues, who were killed by the IRA in an ambush. “We realised then how tricky this was,” he says in a matter-of-fact way.

Despite the undercurrent of violence, he is nonetheless keen to dispel the image of “bone-headed” army officer. “There’s plenty of sensitive ones around that are highly intelligent”.

In fact, Johnson previously studied at Oxford University and describes joining the crack Parachute Regiment as though it was the next logical step from academia.

He became a captain and seemed destined for a long army career, until the birth of his son, Tom. He and his wife Chrissy realised that serving in the army while bringing up a seriously disabled child would not be possible as the job involved staying away from home for up to eight months a year.

His move to teaching opened new possibilities, and although he does not use the word ‘mentoring’ it’s easy to see how he might have viewed the job, overseeing the lives and intellectual development of scores of children.

After retiring, the quest for a new challenge was a constant and he signed up to a writing course 10 years ago (“I wanted to find something I could improve at at a ripe old age of late sixties and into my seventies.”).

His deep-dive into writing has been a rewarding experience, and if teaching came at an opportune time in his working life, it appears writing did the same for him in retirement.

“When you’ve been driven every day by a job that you loved and then you find something you can do and which you can improve at is very cathartic.”

His next writing project - an anthology of poems - confirms the view that he is not averse to taking risks, either.

“It’s a new challenge - it took me three years to write ‘Plot One’,” he says with a disarming laugh.

Now living happily in Stoke Gabriel, he muses on how the decision he made all those years ago to go into teaching had a positive knock-on effect.

“Tom’s now 50 years old and although he’s in a wheelchair he is totally independent and teaches philosophy and religious studies at a large comprehensive. That for me is a real help to me - the fact both my sons went into teaching means it can’t have been that bad having a dad who was a teacher!”

The proceeds of the novel will go to his preferred charity, The Millfield Foundation, which gives life-changing scholarships to young people.