Brianne Sommerville studied English literature and theatre at Queen's University before building a career in public relations and marketing. She traded brand narratives for twisty domestic suspense, writing in stolen hours between her day job and her kids.
Her debut novel, If I Lose Her (2024), and sophomore thriller, What She Left Behind (2025), explore the darker side of domestic life and have been compared to the works of Ashley Audrain and Stacey Willingham.
Brianne lives in King City, Ontario, with her partner and their three children under eight (proof that real life can be just as thrilling as fiction).
Joanna Baker is a first-time mother diagnosed with postpartum depression after a near-fatal mistake brings her under Child Protective Services scrutiny. Experiencing increasing blackouts and memory loss, Jo struggles to understand her condition while fighting to maintain custody of her daughter. As family secrets surface, she must discover who truly has control over her life — before it's too late.
"And why don't I have the faintest memory of this?"
Recently fired and adrift, Charlotte Boyd agrees to oversee renovations on her parents' small-town summer home — a place that holds a tragic past. After discovering an enthralling diary hidden amidst junk the previous owners left behind, Charlotte connects with the author: a troubled teen named Lark Peters who died by suicide at the house sixteen years ago. In a search to uncover the truth, Charlotte must question those closest to Lark and reconcile her own past trauma, because if Lark was actually murdered, then whoever is responsible might be lurking in Charlotte's own backyard.
"How strange it feels to touch a dead person's things."
Praise
What She Left Behind
"Set in a small town where everyone knows everyone else (or do they), WHAT SHE LEFT BEHIND weaves plot twists, dual timelines, family dysfunction, and reckoning with the secrets of a very dark past, all at an absolute breakneck pace."
Ashley Tate, #1 national bestselling author of Twenty-Seven Minutes
What She Left Behind
"Taut like a tightrope, WHAT SHE LEFT BEHIND is a profoundly impactful suspense about a woman who becomes entwined in the decades-old death of a teenager. With an ominous small town setting where secrets are well-hidden, this beautifully written and exquisitely tense sophomore novel kept me pinned to the pages, jaw dropped."
Samantha M. Bailey, USA TODAY and #1 international bestselling author of Hello, Juliet
What She Left Behind
"Brianne Sommerville has done it again! WHAT SHE LEFT BEHIND is a gripping thriller with characters to care about and a story that pulls you in and won't let go until the very end."
Jessica Hamilton, author of What You Never Knew and Don't You Dare
What She Left Behind
"In her signature enticing voice, Sommerville weaves a haunting, heart-pounding mystery where past and present blur, and nothing is as it seems."
Maggie Giles, author of The Art of Murder
If I Lose Her
"Debut author Brianne Sommerville makes a splash in the thriller genre with her captivating, compelling IF I LOSE HER. Sommerville beautifully balances a woman trying to figure out who's putting her child in danger with a deep, raw look at motherhood, marriage, and family that skyrockets in intensity on every new page. A fantastic read!"
Samantha M. Bailey, USA TODAY and #1 international bestselling author
If I Lose Her
"Sommerville captures the bone-deep fears of new motherhood with raw and poignant accuracy — an edge of your seat thriller in which everyone is a threat to her child, possibly even, herself."
Jessica Hamilton, bestselling author of What You Never Knew
In the Media
Television and podcast appearances · 4 min
Get in Touch
For event bookings, press inquiries, or just to say hello — Brianne would love to hear from you.
Literary Agent
Carolyn Forde, Transatlantic Agency