Mysteries of Unexplored Worlds #18

This issue is an anthology containing multiple stories. "Space Suds" follows advertising genius Ned Hilbert, who creates a product called Space Suds and partners with Professor Cooper to stage an elaborate hoax: a fake Martian invasion designed to unite world governments and prove humanity will fight a common enemy. "The Brain of Professor Mandel" depicts a man with extraordinary mental abilities who becomes a living "Ian Instrument" capable of pure thought, prompting someone to kidnap him and attempt to extract his brain for its superior intellect. Additional stories advertised on the cover include "Hail Hero in the Window," "The Forbidden Formula," and "The Man Who Didn't Belong."