Planning a function or a special occasion? We have the answer….
Layered with tension, shocking twists and creeping unease, WHAT YOU DON’T KNOW is the gripping new psychological thriller from award-winning Phillip Island author Sandi Wallace.
WHAT YOU DON’T KNOW is set on Wyeebo Island between French Island and Phillip Island and follows Tess and Joe, a couple who appear to be living the dream. Tess writes children’s mystery books and loves having her husband home on weekends. He has it all, a travelling job he excels in and a wife he adores.
But how well do they really know who they’re married to?
A prowler in Tess’s neighbourhood triggers trauma over her best friend’s unsolved death – and dread of history repeating. Tess does odd things- she can’t remember, and Joe acts cagey. They each have secrets that converge with the abduction of a young local woman.
Who can they trust when they don’t trust each other, or themselves? With nobody and nowhere safe, can Tess stop what she doesn’t understand… or will somebody else die because of her?
WHAT YOU DON’T KNOW is Sandi’s seventh novel and is inspired by her own personal experiences.
‘My dream of being a crime writer began when I was around six,’ she said. ‘I’m now living that dream on Millowl / Phillip Island—fortunately far more sedately than Tess does on Wyeebo Island.”
Sandi obtained permission to use the word Wyeebo, which means ‘small island’ in the Boonwurrung language. It was a way to pay her respects to the Boonwurrung People, the Traditional Owners of the land where this story is set.
She said the fictional location of Wyeebo Island is set between French Island and Phillip Island and is surrounded by landscape familiar to locals and visitors to the area.
The novel was shaped by true events including a personal health challenge during the pandemic and Sandi’s sea change to the island.
Though just recently released at the end of 2025, WHAT YOU DON’T KNOW has already attracted strong praise from the crime writing community and avid readers.
Award-winning thriller author Alan Carter describes it as ‘an unsettling, claustrophobic tale of small-town secrets, with tension ramped inexorably towards an explosive climax.’
Ngaio Marsh Awards finalist Nikki Crutchley calls it a true ‘just one more chapter’ read.
‘A web of secrets and lies kept me turning the pages as Sandi Wallace took me on a deliciously tense and suspenseful journey,’ Nikki said.
Wallace is no stranger to acclaim. Her career highlights include wins and commendations in the Scarlet Stiletto Awards, multiple finalist placings for her short crime fiction, and two popular collections, ON THE JOB and MURDER IN THE MIDST. She has also written four rural crime thrillers in the Georgie Harvey and John Franklin series—TELL ME WHY (winner of the Davitt Award Readers’ Choice and shortlisted for The Davitt’s Best Debut), DEAD AGAIN, INTO THE FOG, and BLACK CLOUD.
Published by international publisher Next Chapter, WHAT YOU DON’T KNOW is available now in paperback, e-book and hardcover, with large-print paperback and audiobook editions coming soon. It can be purchased through a wide range of physical and online retailers, including Turn the Page in Cowes.
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Unwind acknowledges the Traditional Custodians of the land – The Bunurong People of the Kulin Nation and we pay our respect to Elders past and present.
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