Our hero, having discovered true love, has enough to worry him even before shadowy figures glimpsed late at night and a series of fatal accidents convince Falco and the Emperor that traitors are still conspiring and must be brought to book. Mourning Helena, who seems to want to abandon him, Falco sets off on a ramble through the Roman holiday spots, acquiring a goat on the Toe of Italy and accompanied around the Bay of Naples by his best friend Petronius – a member of the official police force who has somehow won himself a reputation as a ‘respectable family man’. This is the story in which the author learned never to kill off useful characters – but in fiction there is always a solution.

This is the one with the ‘Pompeii’s a place that intends to last’ joke.