Written while Tarkington was living in Paris in 1907, The Guest of Quesnay tells the provocative story of Larabee Harmon, the most profligate rich American in France, who is involved in an open extramarital affair with a Spanish dancer, Mariana. After the illicit lovers are critically injured in an automobile accident, Mariana mysteriously disappears and Larabee begins a slow convalescence under the care of a famous psychiatrist.