It's almost Christmas, and Gwinny Tuffel's thoughts are on what she'll buy for DI Birch and whether she can adopt another furry friend. But sorting through her late father's papers leads her into his mysterious past, pointing to an enigmatic liaison with someone now living in a Somerset commune. Gwinny and DI Birch find themselves unexpectedly snowed in with a group of retired spies, along with an energetic Cocker Spaniel, and embroiled in a murder case. Will they uncover the culprit and escape in time for Christmas?