Inventor Henry Millikan invites a group of top scientists to his home to witness his latest scientific discovery. First they have to wait for his wife, Helena, who apologizes for her chronic tardiness. Henry finally gets around to explaining that he has invented a way to turn base matter into gold. He demonstrates on a rock from his yard, only to watch it explode in spectacular fashion. The scientists denounce, Henry, nothing that his previous experiments with a perpetual motion machine and a youth-rejuvenation formula were equally unsuccessful. They leave, telling Henry not to invite them again.
Helena tries to console her husband, who asks her to clean up and call him to dinner as he goes to his lab in the basement vault. Later, he comes up and discovers that she has forgotten, and tells her that he's made his great discovery Henry tells her to come down later to his lab, but after several hours work, he discovers that she's late yet again. Going upstairs, he hands her a vial of a brown liquid and says that his discovery will make him famous... and Helena immortal.
Two weeks later, Henry's nephew George Beaumont comes to the house to check up on Helena, who has taken ill. He admits that Helena hasn't responded to any of his treatments for what appears to be a case of food poisoning. Henry tells him not to worry and asks when his wife will die, pointing out that she's always been late. George wonders if Henry has poisoned his wife, and the inventor takes George to see Helena and get an explanation. Dying, she tells George that she took poison but she did it willingly, and that Henry is going to bring her back to life.
Helena soon dies and Henry takes her down to his lab and administers the treatment. He then goes back upstairs where George tells him that he's called the police despite his promise not to. George warns his uncle that he'll be prosecuted for murder, and Henry insists there's no murder victim and Helena will join them in a few minutes. They go back to the lab and George confirms that Helena is dead. Henry says that they should wait, but nothing happens and Helena remains dead. Shocked, Henry goes to his room once he realizes what he's done.
Later, the police arrive and confirm that Helena is dead. George tells them what happened and they go to Henry's room to arrest him, only to discover that he has killed himself. As the detectives check the body, George goes down to the living room, shocked. He hears a noise from behind him: footsteps coming up from the basement. Before he can turn, a corpse-like Helena puts her hand on his shoulder and asks where Henry is, and apologizes for being late again.