Vigilante is an easy and entertaining read with a slight thriller twist that anybody can enjoy.

Author Shelley Harris thinks, however, that you will be able to personally identify with it if “you know what it’s like to look at your life and wish that it was more remarkable.”

The novel follows the life of Jenny Pepper and, to begin, it is not what she thought it would be, but her dream of regaining her autonomy soon becomes reality.

After rescuing a woman in trouble Jenny feels more invigorated than she has in years as an unappreciated housewife and charity shop manager. She cannot bear for that feeling to fade and so takes on the role of a vigilante, but the danger she discovers seems to be more than she can deal with.

Shelley, from Marlow Bottom, has two teenage sons aged 13 and 15 and when I tentatively asked whether the story was somewhat inspired by her own life, she replies: “Oh totally! I hit 40 and started wondering where the remarkable life I’d dreamt of had gone.

“I tried to get out of that way of thinking by cycling around Marlow Bottom and leaving poems around the place. Doing it anonymously was very empowering. I started to think about if a woman was having a mid-life crisis, what might she do that was much, much bigger?”

So to understand how her character might feel when playing the role of a vigilante Shelley decided to do just that. She put on a superhero costume of her own and took to the streets of High Wycombe with the hope of helping others.

Unfortunately, she admits: “I discovered it’s actually very hard. I spent a lot of time walking around in a mask and a cape looking for things to do.

“I saw a woman with a baby in a pushchair who couldn’t make a phone call in a public phone box so I offered to help, the baby cried at me.

“There were no daring rescues, not much was coming up on the streets so I went to a British Heart Foundation charity shop looking for good deeds.”

Despite her experience in reality not quite matching that of her character, who starts out a little unwittingly and then cannot stop, her experiences in High Wycombe formed an understanding that emanates throughout the book.

She explains: “It is a bit like method-acting. I realised how amazing and empowering it is to put a mask on. On patrol as soon as I put it on, I felt calm even though physically your perspective is narrowed and so I thought about the character and how she has a more and more blinkered view of her life.”

Despite the quirky traits of the tale, throughout the book Shelley subtly highlights the sexualisation of schoolgirls as well as the misogyny of comics to make a poignant point and, like the more serious crime thrillers, it comes with a twist that I for one did not see coming.

Published by Weidenfeld & Nicholson