If it’s good enough for Tennessee Williams, it’s good enough for me. *

So, tell me — what was the very first spark that made you think, ‘I need to write this story’?

I’ve always been fascinated by stories that happen to ordinary people with ordinary lives. And the scariest of crime writing really does connect ordinary people to the worst of humanity. Crime novels that have completely pie-in-the-sky characters… and Patricia Cornwell I’m honestly looking at you right now and thinking really… he came back from the dead?!… are sometimes fun to read, but they’re not unsettling, and they don’t give us that feeling that it could be someone we know. I wanted to write a story with believable, realistic characters – which to me means they’re flawed, they make daft decisions and you often despair of them.

Without giving too much away, who’s your favourite character in Witness and why?

I think, in many ways, the novel is about friendship at the heart of it, and so I think Sadie’s friends are my favourite characters… especially because they’re based on strong women who are close to my real heart. We all need the voice of reason behind us – even if we don’t always have the common sense to listen to it, and Liv and Helena, Sadie’s friends offer that. As an ex-teacher myself, I know how important these women will be to Sadie at work – honestly, it’s your teaching team that gets you through the day in school and so these two really are my kind of people.

I’ve got to ask — is there a real-life inspiration behind any of the twists, or is it all pure imagination?

Well, thankfully I’ve never known anyone turn their hand to murder, but there definitely is a real life connection to some of the twists. They’re probably the ones that will have the reader going ‘Yeah, like that would ever happen!’ – life is often stranger than fiction.

What was the hardest scene to write — the one that kept you up at night?

I don’t think there was a particular scene – it’s more the cumulative plotting that goes on. I find writing crime novels to be like trying to unpick a particularly tricky necklace. I find trying to work out all the different elements the bit that keeps me up at night. I often talk the ideas out loud, even just to myself, because sometimes that helps something slot into place.

If you could step into the world of Witness for a day, what would you do first?

Go for a drink with Liv and Helena of course! They’d have all the gossip and would just be brilliant to hang out with. I think I’d give everyone else a wide berth!

Thrillers often make us question what we believe — what’s your own relationship with trust and doubt?

I think I’m a ridiculously trusting person – probably because I’ve led quite a charmed life where people generally haven’t let me down. I can be quite naive when looking at situations, and would always rather believe the best in people than the worst. Maybe I should start being a bit more suspicious… but I think I’ll leave that for my books instead!

Writing a book is a rollercoaster — what surprised you most about the process this time?

I was talking about this with a friend of mine who’s written some fantastic Young Adult novels (Hetty Waite – you can buy her books here) and we both were saying how much we enjoy the way our characters take on a life of their own. You think you’re in control of them, but if you’ve plotted them effectively enough, they become their own person, capable of independent action. When I first started writing Sadie, I had no idea she was going to end up doing half the things she did… but then she grew and became a whole person!

What’s the one line or moment in the book that still makes you shiver when you read it?

Ooh, a tricky question to pin down to just one. I’d have to choose a few – mostly ones around Sadie not trusting her own judgement such as ‘How long can I keep seeing something that doesn’t seem to be there?’ When you’re questioning yourself, and your own brain… where do you go next? If you can’t trust yourself, how do you trust anyone else?

I’m curious — what’s your writing ritual? Do you need candles, coffee, complete silence… or chaos?

I need a space, and I do like a candle burning – it smells nice and it heats my room because the radiator doesn’t work brilliantly! I’ve got my desk set up really nicely now, which is great for editing. For writing afresh though, I still find I write best when I’m elsewhere – a coffee shop or a hot desk – it seems to force me to concentrate instead of getting distracted.

Finally, if you could whisper one secret about Witness to your readers before they open it, what would it be?

Firstly, I want my readers to know that Witness is a different kettle of fish than Between the Lines – you might still be able to detect my voice in there, because no matter what I do I’m always 100% me in writing and speaking – but the story itself is very different so be prepared for that.

Otherwise, I want readers to really think about what they would do in Sadie’s shoes – it’s easy to judge her, but would we be able to do anything differently!

Witness is available for pre-order now on Amazon!

* Read the back of A Streetcar Named Desire!