What happens
Superman, secretly the reporter Clark Kent, investigates an abandoned factory after a poisoned candy box nearly killed Jimmy Olsen. Accompanied by Perry White, editor of the Daily Planet, Kent drives through the dark toward the site, where Max Heller and a mysterious woman known as the Leopard Woman have gone to an underground hangar holding an experimental folding-wing plane. Heller and his companion argue over whether to destroy the plane, and a shot is heard. Kent and White descend through a trap door and find Heller badly wounded, murmuring about the Leopard Woman and urging someone to tell her something. Kent decides to rush Heller to a hospital as Superman, knowing his chances of survival are slim. The episode is the fourth part of the 1942 serial, first aired on January 19, 1942.
An abandoned factory in the countryside outside Metropolis, with an underground hangar and a dark corridor beneath it, and the city of Metropolis itself.
Characters: Clark Kent, Superman, Perry White, Max Heller, Leopard Woman, Jimmy Olsen, Lois Lane
Listen for: Heller's dying words about the Leopard Woman, and the moment Kent decides to carry him to the hospital as Superman.
Written from the episode itself; it never gives away the ending. Every recording is remastered for the stream: cleaned of rumble, hiss and mains hum (and the old TV whine where we found it), then levelled in two passes to steady broadcast loudness, so one show is never quieter than the next.