Ellie Christie is thrilled to begin a new chapter. She's recently returned to her tiny Colorado hometown to run her family's historic bookshop with her elder sister, Meg, and their beloved cat, Agatha. Perched in a Swiss-style hamlet accessible by ski gondola and a twisty mountain road, the Book Chalet is a famed bibliophile destination known for its maze of shelves and relaxing reading lounge. At least, until trouble blows in with a wintry whiteout. A man is found dead on the gondola, and a rockslide throws the town into lockdown--no one in, no one out.

The victim was a mysterious stranger who'd visited the bookshop. At the time, his only blunders had been disrupting a book club and leaving behind a first-edition Agatha Christie novel, written under a pseudonym. However, once revealed, the man's identity shocks the town. Motives and secrets swirl like the snow, but when the police narrow in on the sisters' close friends, the Christies have to act.

Although the only Agatha in their family tree is their cat, Ellie and Meg know a lot about mysteries and realize they must summon their inner Miss Marple to trek through a blizzard of clues before the killer turns the page to their final chapter.