Gillian McAllister was born on 28 February 1985 in Sutton Coldfield and grew up in Tamworth, in the West Midlands. She read English at the University of Birmingham, earning a 2:1 BA Hons, before converting to law and completing both the GDL with commendation and the Legal Practice Course with distinction. That legal grounding didn't lead her away from fiction. She wrote in the evenings and on commutes throughout her years practising, finishing her first full novel — unpublished — while ill with glandular fever. The habit stuck, and eventually the writing took over entirely. She now lives in Birmingham and writes full-time.
Her debut novel, Everything But the Truth, was published by Michael Joseph, an imprint of Penguin Random House UK, in 2017. It entered the Sunday Times Bestseller List at number six in its first week — a strong opening that set the tone for everything that followed. Each subsequent novel has charted in the top twenty, with How to Disappear and That Night both breaking into the top ten. That Night was also selected for the Richard and Judy Book Club and reached number one on the Kindle Store.
The book that brought McAllister to a genuinely global readership was Wrong Place Wrong Time, published in 2022. Built around a time-loop premise — a mother watches her son commit a crime, then wakes to find herself travelling backwards through the days before it — the novel became a Reese's Book Club pick, debuted at number four on the Sunday Times Bestseller List and number two on the New York Times list, and was selected for the BBC Radio 2 Book Club. It was also named Sunday Times Thriller of the Year. The novel has since sold into 40 foreign territories, and McAllister's work as a whole has been translated into 40 languages.
Just Another Missing Person followed in 2023, centred on a detective drawn into a morally impossible situation during a missing persons case. Famous Last Words, published in 2025, put a marriage at its centre and became both a Sunday Times and New York Times bestseller. Her tenth novel, Caller Unknown, published in 2026, was selected for the Read With Jenna Book Club in the United States. Several of her novels have been optioned for television and film.
McAllister writes psychological thrillers that are consistently built around a single, sharply defined moral dilemma. The questions her books pose are domestic and immediate — would you cover up a crime for someone you love? How well can you ever truly know your closest relationships? — but the plotting is inventive enough to prevent them feeling formulaic. Each novel is a standalone, though readers who move through the back catalogue will recognise her particular interest in the pressure that secrets place on families, and in the legal and institutional systems people turn to when those secrets break.
Her background in law runs through the work quietly but unmistakably. It shows in the procedural accuracy, in an understanding of how evidence is gathered and how cases are argued, and in the specific kind of moral precision that legal training tends to produce. The thriller elements are always grounded in character rather than spectacle, which is part of why her books tend to stay with readers long after the final page.
Away from her novels, McAllister co-hosts The Honest Authors Podcast with fellow author Holly Seddon, a series noted for its candour about the realities of publishing and the writing life. She is married with a son, born in October 2022.
