Paris, 1892. The American historian Henry Adams, grandson of one President and great-grandson of another, is looking for Miriam Talbott, a young American woman studying in Paris. Miriam is alive in ways Adams can scarcely remember being: bright, beguiling, talented, and attractive. She draws him out of the "posthumous" life he has led since the suicide of his wife, Clover, seven years before. But when he goes looking for Miriam, no one at her given address has seen her.

And when another woman's body is fished out of the Seine and identified as hers, Adams knows she is in trouble and needs his assistance. Adams soon discovers that Miriam's disappearance is somehow involved with the great Panama Affair that threatens to engulf France. Before it went bankrupt, the French Panama Canal Company had bribed nearly half the members of the Chamber of Deputies to gain legislation favorable to its interests.

Now one director of the company has been found dead; other directors flee; and for a week, the entire city awaits the revelation of the names of the chequards, the long list of deputies witless enough to have accepted their bribes in the form of checks.