AMC says it is developing a companion series to its Georgia-set zombie apocalypse drama \"The Walking Dead.\" Robert Kirkman, Gale Anne Hurd and David Alpert are on board as executive producers, with AMC Studios set to produce the as-yet-untitled companion series, which has a target on-air date of 2015. \"Building on the success of the most popular show on television for adults 18-49 is literally a no-brainer,\" Charlie Collier, AMC\'s president and general manager, said in a statement Monday. \"We look forward to working with Robert, Gale and Dave again as we develop an entirely new story and cast of characters. It\'s a big world and we can\'t wait to give fans another unforgettable view of the zombie apocalypse.\" \"After 10 years of writing the comic-book series and being so close to the debut of our fourth, and in my opinion, best season of the TV series, I couldn\'t be more thrilled about getting the chance to create a new corner of \'The Walking Dead\' universe,\" said Kirkman. \"The opportunity to make a show that isn\'t tethered by the events of the comic book, and is truly a blank page, has set my creativity racing.\" Co-starring Andrew Lincoln, Norman Reedus and David Morrissey, Season 4 of \"The Walking Dead\" is to begin on AMC Oct. 13.