Shamrock O'Day, a poor laundress dreams of a marrying a rich man. Her neighbour Tom McGuire, the chauffeur of socialite Iris van Suydam, is secretly in love with his mistress. On the other side of the city, Iris is not happy with her pampered life and she dreams of living in a vine-covered cottage. Her rich young fiancé Richard Prentiss is just as tired of women of her class as she is bored with men of his.
        When Shamrock comes to deliver laundry at Richard's house, she meets him by chance and he falls in love with her. He proposes to drive her home and tells Iris to wait for him. She decides to go for a picnic with her chauffeur Tom and, after letting her car being crushed by a train, falls into Tom's arms. In the evening, Richard provocatively dances at a formal party with Shamrock, which causes his sister Elsie to announce her brother's engagement to Iris. Tom, having read the announcement in the press wants to leave Iris's service but she tells him she wants to marry him. The fact that her rich uncle clear all her allowances and she was left without a penny does not deter her. As soon as he hears the news, Richard decides to marry Shamrock.
        Soon, Shamrock, who feels she is despised by Richard's family and friends is almost as desperate as Iris who must live in a tiny apartment next to a railway and spend her time cooking and cleaning. She decides to hire Tom as her chauffeur despite Richard and Iris's opposition. One evening, they go together to Coney Island. When they come back, they find Richard and Iris waiting for them. Iris tells Richard they are too different to live together. While Richard and Iris try to persuade their spouses that they love them, a fire breaks out. Richard saves Iris's life.
        Seven years later, Shamrock and Tom are happily married and have several children, while Richard and Iris are still pondering whether it is time to mend their broken engagement.