The Dead of Night

Amy and Dan have managed to rescue one of the Cahills kidnapped by the Vespers, but the remaining hostages are still in peril. Their search for the next ransom item leads Amy and Dan to Turkey and then to Italy where a visit to the site of an ancient disaster changes everything. The Vespers are far more dangerous than the siblings ever imagined and, even worse, it looks like they have an undercover mole posing as a Cahill.