Carl Brauer, a blind musician, has a daughter who is a nurse at the city hospital. She and the house physician, Dr. Harvey, are interested in each other. Frank Hoag, a wealthy but unfeeling husband, brings his wife to the hospital to be operated upon, and soon after leaves to keep an engagement with an adventuress. On the way out he happens to pass Miss Brauer in the corridor and attempts to flirt with her. On his next visit before the operation, he finds Miss Brauer taking his wife's temperature. The latter introduces them. Hoag, in order to make a hit with the nurse, shows great solicitation for his wife. In the meantime a famous specialist, who happens to be in the city, brings a wealthy blind patient to the hospital to be operated upon. The operation proves successful. Mrs. Hoag, however, dies. Hoag pretends deep sorrow. The nurse is very sympathetic. Later the husband's true character is revealed by showing him drinking at the club and dining with different women. By chance he happens to see Miss Brauer go into a surgical supply house and decides to wait for her. She has called for a hypodermic needle which she left to be repaired. The druggist demonstrates that the needle is in working condition and she requests him to fill it as she desired to use it on a patient who is suffering intense pain. He does so. She exits, meets Hoag, who asks to accompany her home. She agrees. Meanwhile the blind father of the girl has gone out for tobacco and falls into a trench. The ambulance is called. Dr. Harvey responds. By this time Hoag and Miss Brauer have reached home. She invites him in and calls for "daddy." Hoag thinks she is bluffing about "daddy," and makes advances. When he roughly forces her back she reaches for the needle on the table and thrusts it into his arm. He backs away and laughs. Dr. Harvey arrives and finds old Brauer not seriously hurt. The latter insists on going home. Dr. Harvey walks with him. Just before they enter Hoag begins to feel the effects of the needle, grabs the nurse who is trying to get to the door, is overcome and collapses. Dr. Harvey enters with her father. Doctor Harvey sees the body on the floor and picks up the needle. They explain to each other in pantomime orders not to alarm Brauer. Hoag is removed to the hospital. When he comes to at the hospital Dr. Harvey stands over him, gives him a tongue lashing and tells him to get out before he is arrested. Mr. Thompson, the wealthy gentleman who was successfully operated upon for his eyes, calls at the hospital and makes out a substantial check to Dr. Harvey, his assistant and the nurse who attended him. The nurse sees this from a distance. She asks Dr. Harvey to interest the specialist in her father's case. The specialist advises Dr. Harvey how to handle the case. The operation is successfully performed. Dr. Harvey calls to take Miss Brauer out one evening. They are seen in a café together by Hoag, whose interest in the girl is reawakened. The next afternoon while drunk he decides to visit Miss Brauer. In the meantime Dr. Harvey and Miss Brauer have an afternoon off. She is home expecting the doctor to take her for a spin in his car. The blind father goes to take a nap and Hoag forces his way in. The old gentleman hears sounds of a struggle. Old Brauer goes to a bureau and gets a revolver but realizes that without his sight it is hopeless for him to try to help his daughter. The old man knows it is too soon to remove the bandages, but prays for momentary sight in order to protect his daughter's honor. He tears the bandages off and sees dimly. He shoots Hoag through the curtains and rushes to his daughter's grateful arms. Dr. Harvey hears the shot outside and runs in. "God blessed me with providential sight to protect my daughter's honor, let the darkness come," the old man explains. He goes hopelessly blind again. Dr. Harvey cares for them both.