Bill Trent, a Canadian soldier during World War I, says goodbye to Colette Dubois, the dressmaker of Lunéville, and leaves for his headquarters in Paris, vowing that they will wed as soon the war is over. He promises to return to Lunéville that night, but once in Paris, he is ordered by his colonel to go to Montreal, his hometown, as peace will be announced at any moment. When Bill does not arrive as scheduled, Colette realizes that he has left her for good. She sadly packs her things, telling her friend, Anne Trepied, that she cannot be happy in her old life without him, and vows to support herself as a traveling cabaret and music hall singer. Some years later in London, Colette, performing as Nadia Petrova, World Famous Russian Singer, has attracted the attention of the wealthy Lord Charles Penfield, who proposes that they elope. She explains to him that she is not a titled Russian, but a French dressmaker, and that she took on her present identity after she went to America in search of someone and attracted an agent while singing a song in a New York restaurant. Penfield is not fazed, and Colette is tempted to go with him. However, when she sees a headline about Bill, who is about to wed a Parisian heiress, she goes to Paris and, as Nadia, opens an account at the bank that Bill owns with his old French war buddy, Gaston Dupont. Nadia flirts with Gaston and arranges to have dinner with the two men. After getting rid of Gaston, she carouses drunkenly with Bill, who finally passes out as he declares his passionate love for his newfound Russian temptress. Colette has her chauffeur Raskolnikoff drive the unconscious Bill to Lunéville, where the next morning he is arrested as he awakens in front of the church. Leaving the police station, Bill passes Colette's shop and asks her for some food before realizing that she is his old love. Colette confesses that she still loves him, but Bill, now smitten with the exciting "Nadia," confides that he no longer loves Colette. She lends Bill money to return to Paris and then promises Anne that she'll make him pay for betraying her. Bill tells Gaston that he won't marry the Parisian heiress, whom he has never loved, and because of the subsequent scandal and Gaston's anger that Bill has stolen Nadia from him, Bill resigns from the bank. Colette, as Nadia, follows Bill, and he declares his passionate devotion. She replies that she finds love boring, takes him on a shopping spree and spends all his money. Later that night, Bill, despondent because Nadia never arrived for their dinner engagement, receives Colette, who visits him on the pretense of having him hold for her a cash inheritance. He invites her to stay at his rooms, and she gets him to kiss her, hoping that he will find her lips as appealing as Nadia's, but a chauffeur interrupts with a message from Nadia. Bill at first refuses the message, and Colette is about to confess her ruse, when he is no longer able to control his desire for Nadia and calls from his window for her chauffeur to return, but he is too late. After Bill auctions his furniture, Colette, as Nadia, declares her love and her desire to run away to Monte Carlo with the now penniless Bill. He rebuffs her and goes to Lunéville, where Colette waits at the shop with Anne. From behind her bedroom door, she begins to sing Nadia's Russian song when Bill enters. In Nadia's voice, Colette tells Bill that the two women are in the room together and, in Colette's voice, says that he must choose between them. He says that he must first find himself, but afterward says that he wants Colette, if she still will have him. After she unlocks the door, he enters to find Colette, who then reappears wearing the blonde wig of Nadia. Realizing the ruse, Bill says that he does not know if he should kiss Colette or spank Nadia. She encourages him to do both, and he says he will all his life and then kisses her.
