"Once upon a time, a psychologist helped build the [comic book] industry, and in the 1950s, a psychiatrist wrecked it," says Travis Langley, Ph.D and author of Batman & Psychology in this bonus mini-documentary.

Langley explains that these two doctors saw the potential of comic books to be very influential and reach large audiences -- and took very different stands against that. Dr. William Moulton Marston created Wonder Woman and used the pages in his comics to spread his ideas that woman could be leaders in love and power.

Dr. Frederic Wertham, however, saw the potential for comic books to sully the minds of young children with what he perceived to be overarching themes of homosexuality. In his famous 1954 book Seduction of the Innocent, "He outright called Wonder Woman the lesbian counterpart of Batman," Langley explains. Wertham suspected Wonder Woman's lack of husband, children and working in the home belied a deeply sinister idea that women could be more than wives and mothers.

Ten months after Marston died, Wertham led a symposium attacking comic books, which damaged the industry greatly for years to come.

Learn more about how two influential doctors changed the comic book industry forever.

Watch the latest episode now on amc.com and AMC apps for mobile and devices.

Robert Kirkman's Secret History of Comics airs Mondays 10/9c.  To get more exclusive extras, sign up for the Robert Kirkman's Secret History of Comics Insiders Club.