Captain Marvel (DC Comics) abilities. Based on book sales, the character was the most popular superhero of the 1940s, outselling even Superman. Fawcett expanded the franchise to include other "Marvels", primarily Marvel Family associates Mary Marvel and Captain Marvel Jr., who can harness Billy's powers as well. Captain Marvel was also the first comic book superhero to be adapted into film, in a 1941 Republic Pictures serial titled "Adventures of Captain Marvel". Fawcett ceased publishing Captain Marvel-related comics in 1953, partly because of a copyright infringement suit from DC Comics, alleging that Captain Marvel was a copy of Superman. In 1972, DC licensed the
Adventures of Captain Marvel this as one of the most outstanding of all serials and Republic's "masterpiece". He writes that Tyler's "striking performance...remains in thousands of minds as the most memorable serial hero of all time – bar none". The characters of Betty Wallace, Whitey Murphy, and John Malcolm all appeared in the Fawcett comics in the 1940s, beginning with "Capt. Marvel And The Temple Of Itzalotahui" ("Whiz Comics" #22, Oct. 3, 1941) featuring Murphy and Malcolm; Murphy made several appearances in the 1970s DC Comics incarnation of Captain Marvel, as featured in the comic series "Shazam!" and "World's Finest Comics". Fawcett also published