Susan, a young girl, the support of her old uncle, earns her living in Madame Millet's fashionable shop. She almost loses her position through her rebuff of the advances of Madame's son, but the arrival of a rich customer renders he services as model necessary. The customer, Mrs. Luckett, a parvenu, struggling desperately to get into society, is struck by Susan's beauty and ladylike bearing, and when a Countess, whom she intended to use as an entering wedge into society, fails to appear, she prevails upon Susan to assume the role of Countess for a night. Susan is a great success and society goes mad over the titled lady. Mrs. Luckett is delighted and insists that Susan continue to play the role. At first Susan refuses, but Mrs. Luckett's pleas and the sudden death of her uncle cause her to change her mind, and she decided to go through with the part. As the Countess, Susan wins the heart of Clavering Gordon, a wealthy and attractive young bachelor. Mrs. Luckett had hoped to "land" Gordon as husband for her daughter, Ninon, and she resents Susan's rivalry. She tells Susan that the disappointment of losing Gordon is killing Ninon, and urges her to go away. Though now deeply in love with Gordon, Susan decides to sacrifice her own feelings to save Ninon. She is about to leave when La Salle, Mrs. Luckett's scheming social secretary, tells her that Ninon is a confirmed drug fiend, and would only ruin Gordon's life. He persuades Susan that she owes it to Gordon to marry him, and save him from Ninon and at last Susan is won over by his arguments. Just before the marriage ceremony, the scheming secretary reveals his true motives. He demands a large sum of money from Susan on penalty that, if she refuses, he will reveal to the assembled wedding guests that she is not a Countess, but a poor working girl and an impostor. Susan is dismayed. Determining that she will go no further with the deception, and scorning the secretary, she rushes into the midst of the wedding party and confesses all. Before the astonished Gordon or any of the other guests can stop her, she disappears. Seeking to forget he sorrow and unhappiness, Susan becomes a nurse and by her sweet unselfishness, wins the love of all whom she meets. After Susan disappeared, Gordon searched in vain, and finally despairing over the results and giving up all hopes of ever finding her, her marries Ninon, in the hope of reforming her. His hopes are vain, for with the years Ninon has grown continually worse, until she has become a shattered wreck. Susan is called upon to nurse her, and though town with conflicting emotions, when she learns that Ninon is the wife of Gordon, the man she loves, Susan tries desperately to save the drug-crazed woman. After a fierce struggle, the maddened Ninon succeeds in blinding Susan with a pair of scissors and then flings herself from the window to her death in the court below. Gordon meets the blinded Susan, and after a brief courtship, the two are married. In their great love they are rendered doubly happy by indications that Susan's sight is about to be restored.