Adam Banting, a somewhat aimless young scholar at Cambridge University, is called to his professor's office one afternoon and assigned a special summer project: to write a scholarly monograph about a famous garden built in the 1500s. Dedicated to the memory of Signor Docci's dead wife, the garden is a mysterious world of statues, grottoes, meandering rills, and classical inscriptions. But during his three-week sojourn at the villa, Adam comes to suspect that clues to a murder are buried in the strange iconography of the garden: the long-dead Signor Docci most likely killed his wife and filled her memorial garden with pointers as to both the method and the motive of his crime.
As the mystery of the garden unfolds, Adam finds himself drawn into a parallel intrigue. Through his evolving relationship with the lady of the house - the ailing, seventy-something Signora Docci - he finds clues to yet another possible murder, this one much more recent. The signora's eldest son was shot by Nazi officers on the third floor of the villa, and her husband, now dead, insisted that the area be sealed and preserved forever. Like the garden, the third-floor rooms are frozen in time. Delving into his subject, Adam begins to suspect that his summer project might be a setup. Is he really just the naive student, stumbling upon clues, or is Signora Docci using him to discover for herself the true meaning of the villa's murderous past?