The Taint plot
The dissolute Frank Boward forces his attention on Mabel Stuart, who detests him. Bert, Mabel's brother, returns home from a visit to his college friends, bringing Arthur Easton with him. Mabel and Arthur are quickly drawn to each other. Mystery surrounds Mabel's mother, and the daughter begs her father to tell her who her mother was, but he refuses. Frank, meanwhile, becomes jealous of Arthur. The Stuarts throw a house party, at which Frank and Arthur are guests. Frank, aware of Mr. Stuart's secret, hatches a plan to win Mabel as his wife.