When a renowned disease expert and Russian defector dies mysteriously during a global affairs conference in Purity, Maine, the tight-knit band of former spies in the Martini Club once again sees their quiet coastal retirement interrupted by international intrigue. And when a waitress at the conference hotel is found murdered, Ingrid Slocum sees chilling links to a disastrous mission that nearly killed her three decades ago. Desperate to uncover the truth, Ingrid is drawn back into the game by a magnetic ex-CIA colleague --- and former lover --- who was with her on the long-ago doomed mission. He convinces her to join him, and together they head to Amsterdam to track down her would-be killer. But a clandestine network of assassins is intent on stopping them.