One of the most controversial storylines in The Walking Dead's storied history — and it has had several — was the decision in Season 1 to send Rick Grimes (Andrew Lincoln) and his group to the Center for Disease Control. The comic on which the show is based has never come close to explaining the source of the zombie plague that's pretty much destroyed Earth, nor did it ever get anywhere close to the CDC. So when the Grimes Gang encountered Dr. Edwin Jenner (Noah Emmerich), a man working to find the cause of and cure the virus, fans panicked.

They shouldn't have, of course. Jenner revealed one key piece of info: everyone on Earth was infected with the zombie plague whether they were bitten or not, but he was no closer to figuring out what caused the disaster than we are to curing the common cold in real life. The CDC blew up, the show moved on and basically never mentioned Jenner or the controversial episodes again.

That is, up until the Season 7 premiere, which has a surprising reference to a key moment from the CDC storyline.

When Rick's group met Jenner, he seemed like their savior at first. But the broken scientist was on his last legs, as was the CDC: a countdown timer revealed that when the headquarters ran out of fuel, it would blow up in order to prevent various viruses and diseases from escaping containment. Jenner locked the doors to his control room and told the group they'd all die peacefully, in a nice, quiet massive explosion. They eventually convinced him to open the doors, and the group (minus one member, who was all like, "enough with the zombie apocalypse already") escaped.

"There's your chance, take it," Jenner told Rick.

"I'm grateful," Rick said to the scientist.

To which Jenner ominously responded, "The day will come when you won't be."

That last phrase, Jenner's last audible line of dialogue on the show (other than a secret whispered Lost in Translation-style in Rick's ear), is also the title of the Season 7 premiere. So is there a connection? Did Jenner somehow escape, and will save Rick's group from Negan's (Jeffrey Dean Morgan) deadly baseball bat? Are we about to find out what actually caused all those zombies????

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Well, no. We spoke to director Greg Nicotero in advance of the premiere and asked about the choice to title the episode with a Season 1 easter egg. He was careful to note that fans shouldn't be looking for plot links back to the CDC storyline, but Nicotero did add that the title was a very specific choice that the Walking Dead team discussed at length. It's a thematic link, not a plot one.

"It really lends itself to the basis of who we are, and when do we stop becoming who we are," Nicotero said of the title. "If the fight is taken out of us... if we decide to give up, or allow ourselves to be ruled by someone else, does that change who we are? And how we handle that and how we stomach it, or accept it. There was a lot of a lot of thought put into that."

It's hard to draw an exact line from Rick's decision to leave the CDC to Negan murdering one of his team in the Season 7 premiere — there have been a lot of terrible events that have gone down in the interim. But this does mark the first time in the series that Rick is utterly and completely helpless, at the mercy of a madman with no clear options on how to stop him. His easiest exit? To just let go and die, just like Jenner did when he couldn't beat the zombie virus.

We'll have to stay tuned to see if Rick takes the same way out (though somehow I doubt it).

The Walking Dead returns to AMC on Sunday at 9/8c.