Lewis Little is a thirteen-year-old boy spending the summer in Paris with his mother, Alice, who is translating the latest medieval romance by Valentina Gavrilovich, the best-selling novelist and exotic Russian emigree. But from the moment Valentina, golden-skinned and exquisitely scented, beckons from a spindly sofa, Lewis floats on a ribbon of Russian cigarette smoke into a delicious new world of passion and intrigue.

At first, the mysteries are of the charming, everyday sort: the origins of saffron sauce, the tastes and names of lipstick. Lewis discusses philosophy with Didier, the existentialist roofer, eats cakes with Valentina's mother, drinks Orangina with Babba, Valentina's maid from Benin, and takes long walks with Valentina's aristocratic dog, Sergei. Most of all, he dreams of Valentina: her delicious laugh, her intoxicating perfume, her silk negligees.

But when Valentina mysteriously disappears and Lewis takes it upon himself to find her, glorious secrets turn ominous.