Murder, blackmail and drug-dealing on the Tiber combine in one of Ngaio Marsh's liveliest and most evocative novels.When their guide disappears mysteriously in the depths of a Roman Basilica, the members of Mr Sebastian Mailer's tour group seem strangely unperturbed.But when a body is discovered in an Etruscan sarcophagus, Superintendent Alleyn, in Rome incognito on the trail of an international drug racket, is very much concerned...