The series was initially a 96-page quarterly anthology, featuring various DC characters – always including Superman and Batman – in separate stories. Comics historian Les Daniels noted that “pairing Superman and Batman made sense financially, since the two were DC’s most popular heroes”. When superheroes fell out of vogue in the early 1950s, DC shortened the size of the publication to that of the rest of its output, leaving only enough space for one story; this led to Superman and Batman appearing in the same story together starting with World’s Finest Comics #71 (July 1954). The title often depicted Batman gaining superpowers as a way to avoid having him be overshadowed by Superman. Lex Luthor and the Joker first joined forces in issue #88 (June 1957).
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