To make ends meet, tough-minded Sarah Austin runs a boardinghouse in Holyoke, Massachusetts, while keeping an eye on Joe, her unemployed, weak-willed husband, and on Alice, her pretty teenage daughter. Displeased by Alice's attraction to Larry Owens, an earnest but impoverished inventor, Sarah encourages her daughter to date Bill Hepburn, who she believes comes from a well-to-do Boston family. When Larry catches Alice and Bill embracing, he displays his jealousy toward his assertive rival and causes Alice to quarrel with him. Joe, meanwhile, decides to invest in an oil drilling scheme promoted by Phelps, one of Sarah's boarders, and steals money from Sarah's secret cache to buy his share. After Sarah discovers her money missing, she suspects Vincentini, a broke boarder who paints portraits of cows, and calls the police. Before the police arrest the painter, however, Joe confesses his deed. Humiliated, Sarah cries and upbraids Joe, who leaves the boardinghouse the next morning determined to find a job. Later that evening, Bill and two other men try to kidnap Joe, mistaking him for Mr. Pennypacker, the local patriarch, and Bill is exposed and apprehended by the police. After he resigns himself to digging ditches, Joe is informed by his jubilant family that his well has struck oil. The suddenly rich Austins then visit Sarah's upper-class sister, Cassandra Palfrey, for a "coming out party" on her Long Island estate. During the party, Sarah becomes "silly" drunk, while Joe tries to interest Mr. Featherstone, a rubber magnate, in Larry's "whistling" tire valve invention, of which Joe is co-owner. Soon after, the Austins hear that their oil well has "dried up" and that their bank account has dwindled to nothing. Poor again, the Austins return to Holyoke, but before they reopen their boardinghouse, Joe receives a telegram from Featherstone informing him that Larry's tire valve idea has been bought and will be worth thousands and thousands of dollars.