This exciting thriller left me ill until the end (in a good way). It tells the parallel stories of Anna, a single mother on an impromptu vacation in Italy, and Stella, her best friend. Very quickly, the reader learns that Anna did not return home when she said she would and had not contacted anyone to explain the delay. This sets up an exciting tension: the reader catches Stella's anxiety as we wait with her for word from Anna; and since we the reader know that something is going to happen to Anna, all the chapters with her are nail-bitingly tense as we hurtle toward that moment when Anna doesn't get on the plane home. Is she having an affair? Has she been kidnapped? Until the last page (and even then), the reader is left wondering: what is Anna after? What is she hiding? Do her friends know her as well as they think they do? And how will it end? A fast, tense read.