THE two sons of the Mayo family, although totally unlike, are bound together by a strong brotherly affection. To Robert, the frail youth fond of books and dreaming, "the far places of the world beckon alluringly." Andrew finds the flowering of all his hopes in the homely tasks of the farm. Both young men love Ruth Atkins, the pretty daughter of a neighboring widow. At the opening of the play Robert is on the eve of departure for a world voyage on his uncle's ship. Only one regret mars his anticipation . . . that he might not have had Ruth's affection. Then unexpectedly he learns that he is the girl's choice, and promptly, albeit somewhat regretfully, gives up his plans for sailing.
Andrew enters the room as Robert is telling his parents and uncle of his changed intentions. The older brother promptly announces the resolve to sail in Robert's place. The subsequent death of his father throws on Robert a responsibility for which he is totally unfitted, and the family gradually sinks into deep poverty.
In a fit of anger and thwarted ambition, Ruth confesses one day to Robert that four months after her marriage she knew her mistake; that Andrew was the one she really loves. Shortly thereafter the prosperous Andrew returns on a visit and, lest the shadow of Ruth should lie between them, tells his brother that he has entirely recovered from any affection he had earlier imagined for Ruth. When he repeats this conversation to Ruth, he cannot understand her hysterical reaction: "You told him that? You actually told him that?"
With the death of their sickly child, Mary, Robert loses his last interest in life. His own death from the tuberculosis that has so long threatened is very near. Ruth pockets her pride and wires Andrew, but it is too late. Andrew arrives just before Robert's death, and Ruth confesses that long ago she had told Robert that she loved Andrew. Andrew, with his affection for his dying brother uppermost in his consciousness, is horrified. He exacts from the girl the promise that she will tell Robert before he dies that she really loved him all the time. When she enters the bedroom she finds that Robert has already passed "beyond the horizon" to the fulfillment of his longings. All Andrew can say as he shakes Ruth roughly is: "He's gone and you never told him! You never told him!"