Otto, a feckless Everyman, tries to adjust to the postwar travails of his defeated nation. Stymied by black-market profiteers and government bureaucrats, Otto begins fantasizing about a happier life at the end of that ever-elusive rainbow.

Arsène Lupin is extremely popular among the population, because he allows the needy to share in his acquired wealth. Before entering the service of the German Emperor Wilhelm II, he removes his vault in Alsace, steals two paintings of old masters, steals valuable gems and calls out to the police prefect to avoid his arrest. But this time he risks being seriously recognized. Lupin must once again use his fine intellect to deftly escape the situation.