Hourman Rex Tyler discovers a chemical that gives him the strength of 50 men and superhuman speed for one hour. By taking his "Miraclo" pill, Tyler fights crime as Hourman. Hourman is a founding member of the Justice Society of America.

Dr. Midnite Dr. Charles McNider, blinded in a brutal attack, discovers he can see in total darkness. Armed with goggles allowing him to see in daylight and blackout bombs blocking out all light, he becomes Dr. Midnite. He is an early member of the Justice Society of America.