The Undercover Soundtrack is a series where I host a writer who uses music as part of their creative environment – perhaps to connect with a character, populate a mysterious place, or hold a moment still to explore its depths. This week my guest might be familiar to you; she’s been here before as Sanjida O’Connell @SanjidaOConnell. She’s turned her hand to thrillers for her latest release and is wearing a new writing persona, Sanjida Kay

Soundtrack by David Gray, Coldplay, The Choir of Young Believers, Massive Attack, Faithless, Sandi Thom

What would you do if you found out that your child was being bullied? Laura, newly divorced and relocated to Bristol, learns that her nine-year-old daughter, Autumn, is being bullied at her primary school. When no one takes Laura seriously, she tries to protect Autumn from the bully – and makes the situation much, much worse. This is the start of my first psychological thriller, Bone by Bone. The story is told from the point of view of the mother, Laura, as well as her daughter.

I found getting into Autumn’s head the hardest part of the process. After all, it’s a long time since I was nine! I wanted to get across what it felt like to be nine as well as the change that being bullied can wreak on a person’s character. Autumn is a shy, sweet child. She loves painting, misses her best friend, Cleo, and likes Mozart and ‘Bark’.

Listening to classical music and looking at Giacomettis didn’t help me understand what it felt like to be Autumn. I started playing Sandi Thom’s I wish I was a punk rocker. Autumn, a slightly other-worldly child, is certainly not a punk rocker – in exactly the same way that Thom sings about punk with the nostalgia of one who never experienced its raw anarchy; aching for a world that never was, whilst wearing flowers in her hair.

Laura, Autumn’s mother, is also shy and introverted. She lacks confidence and is vulnerable and isolated, yet, like any parent, loves her daughter with all her heart.

When Autumn was born, it was as if she recognized her, as if she’d always known that it would be her, this little person who had come to live with her and reside permanently in her heart. It was a love unlike any other: fierce and powerful.

The song that most helped me get into this zone was The one I love by David Gray with its notes of hope and fear.

Because of Laura’s personality and circumstances, she feels powerless to put a stop to some of the terrible events happening to her and Autumn. But at some point in the novel, she needs to overcome her lack of confidence and find inner strength. One of the triggers for this shift was inspired by a Coldplay song, Viva la Vida; a heart-heavy march of reluctant triumphalism.

Bone by Bone is set in Bristol where I live. What I wanted to capture was the juxtaposition of the city as gritty, grafitti-ridden yet woven through with green spaces like The Downs and Narroways, the urban nature reserve where much of the action takes place.

Bristol is a vibrant, culturally-rich and ethnically- diverse place to live; it’s also riven with divisions between classes and races, rich and poor, and I wanted to imbibe the novel with that edginess. The tracks I chose that summed up what Bristol means to me for the purpose of writing are by Bristolian bands, Massive Attack, Safe from Harm and Insomnia by Tricky of Faithless. Safe from Harm seems to embody that uneasiness, its melodic voice and hopefulness undercut with darkness; this track combined with the restlessness of Insomnia were perfect for what I was trying to do with Bone by Bone: create a relentless ratcheting up of tension.

Bone by Bone is set over a period of ten days, covering Halloween and Bonfire Night. It’s grey, cold, icy: I wanted to develop an atmosphere that was taut, tense, sinister. To get me in the right frame of mind, particularly on days when the sky was bright blue and sunshine flooded my office, I would listen to this lyrical, haunting and disturbing single – Hollow Talk by The Choir of Young Believers – now made famous by The Bridge.

The lines began to sing, a shrill, electric song, and then the cacophony of the train roared out of the darkness. The carriages were almost empty and painfully bright as they hurtled along the tracks to the heart of the city. In the fleeting light she saw the meadow, dotted with stunted hawthorns, their twisted limbs dense with red berries, and then a shape: achingly familiar, child-sized, shockingly still.

Sanjida Kay’s debut thriller, Bone by Bone, is published by Corvus Books. She lives in Bristol with her husband and her daughter. Find her on her website, Facebook  and Twitter @SanjidaOConnell.