During the winter of 1950 in the small Cotswold village of Great Rollright, amateur sleuth Gemma Brown starts to suspect that the town’s best baker, Ursula Beurton, is a Soviet spy, tumbling her headlong into a dangerous game of cat-and-mouse that ends with a decision that will lead her to the Undercover Bookshop and change her life forever.

Recently moved to the English Cotswolds, Gemma Brown desperately wants to create the kind of idyllic life she’s read about in her favorite mystery novels, with herself as the leading lady. But fitting in proves difficult as Gemma is more adept at solving mysteries and setting up the village’s first bookstore than she is at baking cakes or grasping social niceties. Nevertheless, she finds a friend in Peggy, a young woman recently moved to town herself, and Ursula Beurton, who is not only the village’s best baker but an enigmatic figure who sparks controversy in the small-town gossip network.

As Gemma spends more time with Ursula, she begins to suspect all those novels are affecting her thinking. The oddities she starts to notice must be her imagination because, if not, they point to something far more dangerous than winning the local baking contest or being placed on the church committee. Could her neighbor be a real spy?

Following her instincts and a few skills learned through fiction, Gemma soon becomes embroiled in an international intrigue involving the village’s mysterious benefactor, Lady Marchmont, MI5, and the KGB. In an unexpected twist, however, Ursula asks Gemma for a favor which may endanger all their lives as their next chapter unfolds in Gemma’s new venture, the Undercover Bookshop.