At AMC’s WonderCon panel for the "Walking Dead" spinoff "Walking Dead: Dead City" Saturday, a teaser trailer was shown that confirmed what Maggie and Negan side by side. Apparently, Herschel - Maggie and Glenn's son - has been kidnapped, and Maggie believes that Negan is the only one that can get him back. The show takes place on a cut-off dead-infested Manhattan Island. The show is set to premiere on AMC Sunday, June 18, at 10/9c.