Summers and Roe, two crooks, learn that Bert Wells, a rich westerner, is in town visiting his married sister, Alice Field, whom he has presented with a diamond tiara. They start out to get the lay of the land. Passing an old clothes shop, Summers is struck with the beauty of Mina, the granddaughter of Crichett, the owner of the shop. She, however, repulses him. She takes her new novel and goes to the park to forget the commonplaceness of everything in a world of her imagination, wherein she figures as “Lady Montmorency.” Mina’s reading is interrupted by a thrilling runaway. She sees Bert Wells rescue his sister, and instantly the westerner becomes the hero of the little East Side girl. That night, Summers and Roe steal the tiara and a beautiful new gown of Alice Field’s. The butler and maid, who are alone in the house, notify the police and describe both the stolen goods and the thieves. The next day, Summers takes the gown to Crichett’s shop, merely as an excuse to see Mina. Later, left alone in charge of the shop, the girl yields to the temptation to put on the gown and walk in the park. In her hurry, however, to avoid her father, who just then returns, she runs off wearing one of Alice Field’s slippers and one old shoe of her own. In the park, she wrenches her ankle, and Bert Wells, who happens to be strolling near, comes to her rescue. She tells him that her name is “Madeline Montmorency” and that she lives at the Plaza. He sees her home. As she is coming out of the hotel, she is confronted by detectives who recognize the stolen gown. In her flight she drops Alice Field’s slipper. Wells finds it and takes it home. Meanwhile, the detectives have traced Mina to the shop, where they arrest her and her grandfather. The butler and the maid are summoned to identify the prisoners. They testify that these are not the thieves, and Wells goes bail for the Crichetts. He gives the old man his card, telling him that if he is in trouble, to call upon him. That evening, Summers and Roe go to the shop and take Mina away by force. Old Crichett phones the westerner. They save Mina from the crooks and prevent the thieves from making their getaway. Summers and Roe go to prison. Old Crichett is killed in the gunfight with the crooks. Later, Mina marries her hero, and they go west to live on his ranch.