When Christopher Reeve’s Superman hit theaters in 1978, it was a new dawn for DC superheroes. Prior to that moment, TV or film adaptations of DC’s pantheon of heroes were overshadowed by the campy success of the Adam West-led Batman of the 1960s. And so, without Reeve’s performance and director Richard Donner’s commitment to verisimilitude and earnest bravery, DC’s heroes may never have truly stepped into the mainstream. Right? Wrong. Three years before Superman hit theaters in 1978, and Christopher Reeve made people believe a man could fly, Lynda Carter’s Wonder Woman hit the airwaves with a pilot TV episode,...