Sequel to Beau Geste and Beau Sabreur. Otis Vanbrugh and his sister Mary leave their despotic father in Wyoming and embark on a Grand Tour of Europe. Travelling on to North Africa, their adventures include discovering what happened the night the Blue Water was stolen and by whom; Otis devotes himself to Isobel, who asks him to search for her husband and Otis' old playmate John, who has disappeared in Africa while searching for his old friends Hank and Buddy. Otis, in love with Isobel, enlists in the French Foreign Legion with the idea of being sentenced to the penal battalion of the French Army of Africa - and so, perhaps, find John and try to rescue him...