Paris in the 1890s. Adam Gould, whose Anglo-Irish father has disowned him, works in a lunatic asylum run by the celebrated Dr Blanche, some of whose patients once starred in France's social firmament and still, when sane, sit at table with distinguished guests. One such patient is Guy de Maupassant. Another is Belcastel, who has taken the blame for a monarchist plot against the Third Republic, then feigned insanity. Madness and uncertain identity drive Adam's story, fuelled by Maupassant's sparkling insights on the matter. Gould falls in love with a married connection of Belcastel's. And things are made no simpler on his return home, when he becomes entangled with a cousin who looks hauntingly like his dead mother...