Doctor Guido, on the eve of marrying the woman he loves, discovers that into his body there has been introduced accidentally the germs of a deadly disease. He cannot manfully go on with his marriage knowing the physical price of such a predestinely woeful alliance. It is for him to disappear and wait for the death soon to come. His lot would be alleviated if he could but tell his fiancée why he could not marry her. But there is one reason why he must leave her, unknowing that his reason for breaking off the match was because he loved her more than love itself. That reason is that his sister is betrothed to the brother of the doctor's bride-elect. If Doctor Guido lets it be known that he is consumptive, his sister's fiancé may suspect that she too has tubercular tendencies, which suspicion might separate them. It is, therefore, necessary for him to seal his lips and go away under a cloud, leaving it to be thought that he had backed out of his pre-nuptial agreement.