The Shadow #55

In "The Black Triangle Gang," Jimmy Gray—secretly the Shadow—finds himself entangled in a mystery when a dead man’s brooch turns up in his train compartment, mirroring one left by a mysterious woman. As the Shadow, he teams up with a masked woman named Stella, whose brooch leads him to a high-stakes party where a priceless necklace vanishes in the dark. Written and illustrated by Peter Chapman, this 1959 Frew Publications thriller blends suspense and intrigue, with Chapman also handling the cover art.