In a gothic tower far from the reach of ordinary men, millionaire Betumaine, masked because of a disfiguring skin condition, lives alone, but for his roses and his manservant, Johnston. When Johnston discovers a discrepancy in the rose accounts, Betumaine despatches auditors to investigate. They find evidence of a small scale embezzlement, and a furious Betumaine summons the accountant, Shane, to be judged.

Meanwhile, Shane's eldest daughter, Sissy, and her husband, Hugo, lament the shame he has brought on the family. When Shane despairs that he is at the mercy of the monstrous Mr Betumaine, they are unsympathetic. But his beautiful and kindly younger daughter, Bella, suggests he go and plead his case with Betumaine in person.

Challenged by Betumaine to explain the discrepancy, Shane admits his error, but insists that he did it not for his own greed or lust, but to benefit his beloved bowling club. He begs for mercy for the club, even if he himself must be destroyed. But Betumaine pronounces him guilty and demands vengeance on him and the club, and sends him away.

Seeing her father so distraught, Bella goes to Betumaine herself. She finds him tending his roses. Approaching him without fear, she marvels at the beauty of his voice, and the power of his mind. She challenges him to admit that he is a man, and charms him with hints of feminine frailty. Finally he agrees to give her father's case further consideration, adding that if she wishes she may visit him again.

After Bella's visit, Betumaine condition worsens and he takes to his bed. Johnston summons a doctor, who suggests 'psychosurgery' to heal his guilt, but Betumaine rejects his prescription. Johnston and the doctor decide another visit from Bella may help.

Bella returns to the tower. Betumaine tells her he has decided to reprieve her father. He confesses his love for her and admits how uncomfortable that makes him. He recounts his charmed childhood and how, after the death of his father, his mother rejected him. When she died, he lived alone and came to despise humanity in its ugliness. Bella rejects him, saying that only when he is a man - selfish, proud, vain and arrogant, but with the one virtue that redeems man's faults - will she accept his love. She leaves without explaining what that one virtue is. As she goes, Betumaine's condition boils up once again, more severely than ever.

Johnston and the doctor call on Bella and tell her that Betumaine is gravely ill. She goes to him at once. He hides his face from her, but when she threatens to leave, he begs her to stay, telling her he needs her. This is what Bella has been waiting to hear, and she kisses him, delightedly. His condition heals itself at once. She persuades him to unburden himself of his guilt by giving his money to her - only women, she tells him, can live with guilt.