Green Lantern investigates murder at the racetrack as foreign powers attempt to prevent the U.S. Government from obtaining a new type of motor.; Discovering that several people in Centerville have been sold worthless property, Sargon tracks down the swindlers.; Dr. Mid-Nite deduces the identity of a killer who is holding the sister of a hit-and-run victim hostage.; The Atom has to find a way to clear Al Pratt of kidnapping charges.