Notes:
The on-sale date is from the publication date recorded in the Catalog of Copyright Entries, Part 2, Periodicals, 1942, New Series, Vol. 37, No. 4.
Character(s):
Captain Marvel [Billy Batson]; Mary Marvel [Mary Batson, aka Mary Bromfield] (Billy Batson's twin sister, introduction, origin); Billy Batson; Sterling Morris; Percy Pill; Sarah Primm (Billy and Mary's nurse, death); Captain Marvel, Jr. [Freddy Freeman]; The Wizard Shazam
First Line:
Folks! Here's a big surprise!...Meet my sister Mary!
Synopsis:
Billy accidently discovers that a young girl appearing on the Station W.H.I.Z. radio show, "The Mental Marvel Quiz," possesses half of a strange locket that he has the other half to, and that her former nurse confirms the fact that Billy and Mary are actually twins!