This holiday special goes back in time to show how Elmo's ancestors--not to mention those of Grover, Big Bird, Bert, Ernie, Oscar the Grouch and Cookie Monster--helped transform "the most unfriendly street in town" into the bright, kind, music-filled place it is today.

This documentary was shot at the George A. Romero Filmmaking Program, with special effects by Tom Savini's Special Make-up Effects Program. The story involves iconic zombie extras from the original Dawn and Day of the Dead who, decades later, find themselves in demand at Pop Culture Comicons. We chase down these zombies to see why these early Romero films resonate so much with fans. Meanwhile, the crew shooting this film set out on a horrifying adventure of their own.