You Know What You Did by K. T. Nguyen

We are delighted to share that our July 2026 pick for the HIF Book of the Month is You Know What You Did by K. T. Nguyen.

You can run from your past… but what happens when it starts rewriting your present?

In You Know What You Did, debut author K. T. Nguyen delivers a chilling, psychologically rich thriller that blurs the line between memory, trauma and reality. Drawing on her own lived experience of OCD, Nguyen crafts a story that is as unsettling as it is deeply human, plunging readers into the mind of a woman who can no longer trust her thoughts, or herself.

When Annie Shaw’s carefully rebuilt life begins to unravel following her mother’s sudden death, long-buried fears and intrusive thoughts return with a vengeance. As reality fractures and suspicion closes in, Annie is forced to confront not only a terrifying mystery, but the generational scars and hidden truths that shaped her.

Dark, disorienting and emotionally charged, You Know What You Did explores the complexities of motherhood, identity and mental health, offering a gripping, twist-filled read that will keep you questioning everything until the very last page.

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An ending that will take your breath away…I loved this book
I.S Berry , The Peacock and The Sparrow

About the Book

Annie ‘Anh Le’ Shaw has everything she once dreamed of: a thriving art career, a beautiful home, a loving husband and daughter. But when her mother – a Vietnam War refugee – dies suddenly, the fragile balance of her life shatters. Her obsessive-compulsive disorder, dormant for years, resurfaces with terrifying force. Only this time, her intrusive thoughts seem to be coming true.

When a powerful art patron disappears, suspicion turns towards Annie. Then she wakes in a hotel room, naked, beside a dead body, with no memory of how she got there. As the investigation tightens and her mind fractures, Annie is forced to confront the ghosts of her childhood and the legacy of her mother’s trauma.

About the author

K. T. Nguyen is a former Glamour magazine editor. K. T. enjoys practicing KravMaga, rooting for the Mets, and playing with her Jack Russell Terrier Alice. A graduate of Brown University, she lives just outside Washington, D.C. with her family. You Know What You Did is her first novel.

FROM K.T.

For years, I lived a double life: chic Glamour magazine editor by day, showering and cowering in my Manhattan studio by night. Portrayals of OCD on television are usually lighthearted – a quirky detective who doesn’t like germs, or a funny neighbor who knocks on the door a certain way every time. However, these portrayals bear little resemblance to the real horror I – and my main character Annie – experienced on a daily basis. I want readers to understand what a debilitating disorder OCD can be and how intrusive thoughts can make you feel like a prisoner in your own body.

Eventually, the birth of my daughter forced me to acknowledge that the war raging in the confines of my skull had real-world ramifications, and Motherhood propelled me to fight and win my battle with OCD, to reclaim my life.

The intergenerational family drama was the most challenging element to write. Mother daughter relationships are often depicted in popular culture as a source of love and support, with minor skirmishes quickly resolved. (Think: Gilmore Girls). But there’s another side to the maternal dynamic: those we trust the most are capable of levying the most harm. In reality, intergenerational relationships are often fraught – especially those under the strain of socio-economic pressures like poverty, forced relocation, and cultural differences. In many refugee families, children, due to their facility with language, shoulder the burden of helping their parents navigate through society. I dedicate my novel to “mothers, daughters, and the daughters who mother.” This is in honor of those who find themselves in the difficult position of taking care of a parent for any number of reasons from old age to mental and physical illness.

Ultimately, You Know What You Did, should take readers on twisty, thriling ride. I don’t want you to know going into the novel exactly what you’re going to get. My favourite psychological thrillers are disorienting – in the best way possible. I’m a huge fan of the genre, and to me the big question isn’t necessarily whodunnit but why and what makes these people tick.