On a cool autumn morning in AD79, at a café bar in Pompeii, a slave we will call Festus was preparing a pot of beans and onions in readiness for the lunchtime rush. The barmaids would soon be arriving — the bar doubled as a bordello and the price for extra favours from each of the women was scribbled on the wall beside the counter.
Stirring idly, Festus noticed that the sky had darkened and a roaring noise was building to the north of the city. Whatever was going on felt threatening; he put down his spoon and fled.
