'The Walking Dead' is a post-apocalyptic horror drama on AMC that follows a main group of survivors living in a world overrun by zombies. It was developed by Frank Darabont based on the Image Comics series of the same name by Robert Kirkman, Tony Moore and Charlie Adlard. 'The Walking Dead' debuted its pilot episode on October 31, 2010 and has since grown to one of television's most-watched series. AMC unceremoniously dismissed Darabont from the series going into its second season, and various reasons, from budgetary issues to creative differences, have been cited. Glen Mazzara replaced Darabont as showrunner of 'The Walking Dead,' though he too would eventually leave over creative differences, leaving Scott Gimple as the current showrunner.