Printed in Daring Mystery Comics #5, June 1940, with 7 color pages. Reprinted in Marvel Masterworks: Golden Age Daring Mystery - Volume 2 (Feb. 2010).
'Whirlwind' Carter detects through his monitors that an invisible planet is heading into the region; it is the Planet of Black Light, the coldest planet in space. Its people are planning to pull Earth out of orbit to freeze everyone and then put it back so the Martians can populate it.