Alice Feeney's debut novel, Sometimes I Lie, was a New York Times and international bestseller. The psychological thriller has been translated into more than 20 languages, and is being made into a TV series by Ellen DeGeneres. It took the British writer and former BBC journalist to unexpected places - not least a prison book club, where her novel was up for debate.
Having never been inside a prison before, I wasn't entirely sure what to expect.
It was a lot like the buildings you see in films and on TV; a maze of tall brick walls, barbed wire, and thick metal bars. It was also noticeably cold, in more ways than one, and the guard behind the reception desk did not look happy to see me.
My fingerprints were scanned, my details were put into "the system" and my belongings were locked away. No phone. No liquids. No sharp objects.
Then I was taken to a room that reminded me of airport security, before being searched and thoroughly patted down. My hands were trembling a little. I admit I felt afraid.
Next came the long walk along cold corridors and down stone steps. The guard escorting me constantly stopped to lock one metal gate behind us, before opening another with the huge set of keys attached to his belt.
My footsteps echoed on the stone floor, and prisoners stared at me as we passed. Eyes full of suspicion and intrigue followed me down the hall, and a faint smell of bleach, fresh paint and stale school dinners permeated the place.
If I had been expecting everyone to be wearing orange jumpsuits, I would have been disappointed. Most inmates wore the prison-issue uniform of green joggers and matching tops, as faded as their smiles. I wondered what my friends and family would think when they found out where I was and what I had done.
My first glimpse inside a cell winded me a little. Behind the metal door, there was an uncomfortable looking bunk bed, and a toilet concealed with a flimsy curtain. On the windowsill, I noticed a hand-drawn card with a blue sky, and just two words written with a child's crayon: "Miss you".
Then I stepped into the library and felt a wave of calm wash over me. Books have always made me feel safe, something to hide inside when the real world gets too dark.
I'm a shy person and I rarely do events. Just the thought of public speaking can bring me out in a rash. I spend most days alone in my shed with my dog and my characters. So when a prison librarian got in touch, asking me to talk about my book with inmates, I surprised myself by accepting the invitation. The tour of the prison before the event was my idea.
My new novel, I Know Who You Are, is a dark and twisty thriller about an actress and a crime that seems impossible to solve. I have always been fascinated by people who lie for a living and pretend to be someone they are not: Actors, authors, politicians… criminals.
I was intrigued to find out why these men wanted to meet me, and it's always flattering when readers enjoy a book, regardless of their current address. Which in this case was HMP Thameside, a Category B prison in South East London.
A paper published by The Ministry of Justice last month says that "all prisoners (in England) are encouraged to undertake reading for pleasure and improve literacy skills".
It also states that access to a library is "a prisoner's statutory entitlement" and that participation in prison education is proven to reduce re-offending.
And, at a time when so many local libraries are under threat, it was a pleasure to step into one that was clearly thriving.
Row upon row of new and old books (mostly donations), in all genres, were just waiting to be borrowed, read and enjoyed. Inmates can also apply to work in the library, as well as take part in the weekly book club.
A circle of plastic seats had been set out, waiting for the audience to arrive. And when the doors swung open, and the inmates entered the room (along with extra security), I was fascinated by the men I met. Old and young sat side by side, and there was an eclectic mix of accents, backgrounds and religious beliefs in the room.
I didn't ask the inmates what they had done - I didn't think it was any of my business. Life can make prisoners of us all, trapped behind invisible bars of our own construction, and only fools think they are free.
I've been very lucky, but life hasn't always been kind to me, and my future could easily have unfolded differently as a result of my past.
My audience that day proved to be one of the most engaged I have ever encountered. They clung to their copies of my novel as though they were something precious. I imagine books must be a wonderful form of escape in prison.
I didn't just meet prisoners that day. I met a teenage son who missed his mum, a husband who missed his wife, and a father who missed the birth of his first child as a result of committing petty fraud.
Roles can always be reversed, in real life as well as fiction. Human beings make mistakes, and the only people with no regrets are liars. Going to prison as a result of writing a novel was a humbling experience, which unexpectedly found its way into my new thriller.
Books can take us anywhere if we let them. They can also set us free. That freedom is something we all aspire too, especially when we lose it.