Based on history, the dentist William Morton figures out how to use ether as an anesthetic for dental work and surgical operations, but he is denied a patent for his efforts.
Eben Frost (William Demarest) buys back a pawned silver medal and gives it to the widow Elizabeth Morton (Betty Field). She recalls how William T. G. Morton (Joel McCrea) learned that Congress passed a bill granting him $100,000; but President Pierce refused to sign the bill and suggested Morton sue. Morton is excoriated in the newspapers and is denied a patent.
Young Elizabeth cries because Morton is leaving medical school to be a dentist; but he asks her to marry. Morton loses patients because of the pain, and he asks Dr. Charles Jackson (Julius Tannen) how to stop pain. Jackson suggests ethers could lower the temperature and to try ethyl chloride. Morton buys some ethers. At home one bottle boils by the fire, and Morton becomes unconscious. Elizabeth thinks he is drunk. Morton learns that the sulfuric ether did it and buys some more. Dr. Horace Wells tells Morton he has used nitrous oxide four times during dental work, but Jackson tells them the idea has been abandoned. At the Harvard Medical College auditorium Wells has Morton help him try it on Homer Quimby, who laughs and then fights with Wells. Morton advises Wells to experiment more. Wells treats a woman with a broken tooth. Morton comes back and tries to revive her. Wells vows not do it anymore, and she lives.
Morton tries to experiment on the dog, but Elizabeth objects. So he uses himself and then cats. Morton advertises painless dental work and promises Frost double his money back if he feels pain. Frost goes mad, breaks things, and is arrested. Morton offers Jackson ten percent for his help, and he advises purer ether. Frost comes back, and Morton gives him ether. Frost goes unconscious, and Morton pulls his tooth on September 30, 1846. Morton becomes the painless dentist and gains patients. Jackson demands 25%. Morton and Frost watch Dr. Warren (Harry Carey) perform painful surgery, and Warren agrees to try it. Wells accuses Morton of stealing his method. Warren waits for Morton amid ridicule. Morton arrives late but puts the patient asleep. Warren says it works. Doctors tell Warren that they must know what Morton's letheon is. Morton claims he wants no money for it but refuses to tell anyone until he gets his patent. Warren says he will operate in the old way. However, Morton visits the girl who is to have the surgery and says that surgery does not have to hurt anymore.
This biographical drama was re-edited after writer-director
Preston Sturges completed it in order to give it a happy ending.
Morton did not get the patent, and this film presents his point
of view on his conflicts over the issue.