On the terrace of an elaborate hilltop apartment overlooking a Central American capital, four people sit making polite coversation. The American couple – an elderly physician and his young wife – are tourists. Their host, whom they have just met, is a young man of striking good looks and charm. The girl, who is his mistress, is very young and very beatufiul. Sitting there, with drinks in their hands, watching the sunset, the Slades seem to be experienced in the sort of fortunate chance encounter that travelers cherish. But amidst the civilities and small talk, one remark proves prophetic. The host says to the American woman: \