Jake and Emily were childhood friends and neighbours. Now in his early twenties, Jake returns to Dunedin from Auckland, where he has been studying after failing to get into medical school. Jake will finally start his medical training, which Emily started a few years before. Emily is now in a relationship with a first-year doctor. Jake and Emily have an enduring attraction. The scene is set for a medical romance. However, Jake and Emily share a secret – one that continues to both bind them together and push them apart – the scene is also set for a harrowing novel about the cruelty of fate and the despair of those at its mercy.

Emily escapes her anxieties by sketching. She wants to create a graphic novel called Double helix dragon – with a heroic main character who can face fate without fear. There is internal fate – the fate of genetics, of blood clots and intercranial haemorrhaging, and miscarriages – intertwined with external fate, the fate of flash floods, suicide, and random accidents. Like Emily, Jake has an escape – surfing: “the ocean moving beneath him, like the ebb and flow of his heart, until he felt as if he and the sea were one and the same, no beginning and no end”. Even in a glass of beer Jake sees the scud of foam as “an outgoing tide”.

Double helix has a romance novel arc: a lost letter, constant misunderstandings over suspected infidelities, over secrets kept and revealed – but through this arc are tragedies. Emily has a hard time at med. school, she has panic attacks, she faints in front of a patient, walks out of her viva. She is haunted by the memory of what she had been able to do as a teenager. Jake takes some energy from the same incident; he copes with the insane stress young doctors are put under. He becomes a conscientious and kind practitioner – the kindness extending to decisions made about patients in pain with no hope of recovery. He sometimes crosses the line of impartiality.

The novel has excruciating depictions of family toxicity. Jake’s father abandoned him when he was eight, leaving him with an ill mother. Emily’s father is controlling and manipulative. Her mother is generous and caring, but there is a sharp side to her, as Jake finds out in a show-down. Emily thinks Jake abandoned her when he went to Auckland all those years ago. But Double helix is not a simple tale – there are always at least two sides to every story. At the heart of everything is the Damocles sword hanging over Jake and Emily. “What you don’t know can hurt you. A lot.”

Both Jake and Emily flirt with suicide – Emily in a hot bath “contemplating the thin blue veins beneath her milky skin”. And when Jake is surfing, he knows it would be as easy to surrender to the sea as ride it. Their characterisations are engaging and moving. And there are other great characters – Kylie, a fellow student and then a firm friend. Jake’s Aunt Ngaire, who shows the calm nurturing side of families. Despite Double helix being unflinching in its depictions of Jake and Emily’s journey, it is a hopeful book with buckets of heart, and I loved it. If it has one message, it is probably that voiced by Kylie: “Fuck fate.”