The Walking Dead is one of the kings of Easter eggs (and ratings) including a lot of them in one episode, it might be a nod to classic horror movies or sci-fi movies, like Robo Cop (in the Strangers ep).
Recently at the Walker Stalker Con in Atlanta this weekend, the same one Aquaman (Jason Momoa) made waves in (LOL get it? Waves?...) due to his Snyder & DC comments, The Walking Dead Director, Executive producer and Special effects master Greg Nicotero revealed an on going Easter egg involving clocks/watches on the show.
In the season 5 return of The Walking Dead we see Rick (Andrew Lincoln) carve a shiv using a chain as he is trapped with his group inside the train car at Terminus
Nicotero explains and elaborates about the easter eggs:
“He’s using Hershel’s watch with the chain,” explained Nicotero. “And then when he leaves, Maggie gets it, so of course if you see Maggie has the chain with the watch. And of course the time is 5:01 on the watch, because that was episode 501.
Nicotero continued, “So if you look at any of the stuff in the show…even when Carol picks up Rick’s watch off the table, it says 5:01. Every episode that we shoot we adjust the time on the watches and the clocks to whatever episode it is we’re shooting.”
The Walking Dead is the smash hit based on the comics of the same name that airs on AMC sundays at 9PM ET