Cécile Rey, whose prosperous family are free people of color, makes friends with Marie-Grace Gardner, a doctor's daughter who has just returned to her native New Orleans in 1853, and persuades her to change places at their separate Mardi Gras balls.

Cécile is enjoying her older brother Armand's return from France and her growing friendship with Marie-Grace, with whom she volunteers at an orphanage, until the yellow fever epidemic theatening New Orleans strikes her own household.