A party of English people are aboard the Euphrosyne, bound for South America. Among them is a young girl, Rachel Vinrace, innocent and wholly ignorant of the world of politics and society, books, sex, love and marriage. She is a free spirit half-caught,momentarily and passionately, by Terence Hewet, an aspiring writer whom she meets in Santa Marina. But their engagement is to end abruptly, and tragically.