This novel revolves around Isàdas Pacha, an Ambassador, and his niece, Mademoiselle Rachel Isàdas. In the Abarian Embassy in London, Isàdas Pacha lay sick unto death. His niece summons' Ruel Bey the first secretary Ambassador to call on his cousin, Dr. Lucien Marillier. When Pacha meets with the doctor, he entrusts a letter of a private nature in his hands. Lucien is to deliver the letter to the emperor and does not want his secretary, Ruel to come in contact with the letter. Pacha fears that Ruel Bey wishes to marry his niece for her social station, rather than for any real love for her. Isàdas Pacha feels that Ruel should be tested in such a way as to protect his niece. The doctor accepts this assignment because it affects Mademoiselle Rachel Isàdas' future. But he did not realize he would become attached to her.
