Upon learning of her husband's impending bankruptcy, Leila, the cold and selfish wife of a Wall Street broker, deserts her husband and takes up residency in their summer home in Seagirt. There, alone and bored, she plans to ensnare young doctor John Ransome as a pastime. Ransome is engaged to Alice Granville, "the sweetest girl in Seagirt," and to break up their romance, Leila feigns illness and sends word to the Granville home for the doctor. Bobby Granville, the youngest boy, hears the call for help and, though sick with a fever, starts out on his bicycle to get the doctor. Leila's ruse goes undetected by Dr. Ransome who becomes infatuated with her. Meanwhile, another lover appears and Leila divides her attention between them both. Leila's husband appears unexpectedly and, discovering her faithlessness, kills himself. This tragedy is followed by Bobby's death, precipitated by his excursion on Leila's behalf, which forces the doctor to realize Leila's treachery and Alice's purity.