Back in November, just weeks before The Walking Dead closed out the back half of Season 6, AMC made the casting announcement fans had been waiting years for: Jeffrey Dean Morgan has come aboard to play Negan. Unfortunately, the announcement also revealed that this villain's presence won't be made until the Season 6 finale, with the actor set to be a series regular in Season 7. On Sunday, the midseason premiere picked up right where the finale's prologue left off, with a group of Negan's Saviors cornering Daryl (Norman Reedus), Abraham (Michael Cudlitz) and Sasha (Sonequa Martin-Green), but a new theory from Walker Culture claims that Negan may have been watching this scene unfold. If you haven't watched Sunday's episode, No Way Out yet, there will be SPOILERS below, so read on at your own risk.

When we last saw Daryl, Abraham and Sasha back in late November, they were outnumbered and outgunned by these unnamed Saviors, who formed a roadblock with their motorcycles. Sunday's episode revealed that they planned on taking all of teh survivors' weapons and supplies before following them back to Alexandria. One of the Saviors was sent to the back of the tanker with Daryl, to see what they had, but, fortunately for Abraham and Sasha, Daryl was able to get the best of this man, taking the rocket launcher Abraham had found earlier this season and using it on the Saviors, resulting in a massive explosion. However, as Walker Culture and Twitter user Vinnie Gorham have pointed out, you can see a car briefly come into the frame in the background, just before the explosion.

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Since we only see the car for a second or two, we have no way of knowing who is actually in the car. But there is plenty of speculation that it is in fact Negan. If this is true, it could mean that he may be hiding in plain sight for the rest of the season, before our first formal introduction to the character in The Walking Dead Season 6 finale. With a show that is scrutinized and pored over as much as The Walking Dead, it's believed that this car briefly came into frame on purpose for fans to discover, and it wasn't just some sort of logistical error where a car mysteriously comes into frame for a few seconds.

The impending arrival of Negan has many fans worried about the fate of Glenn Rhee (Steven Yeun), who had his own death scare of sorts earlier on this season. Negan is introduced in the 100th issue of The Walking Dead, where he and his group took Rick and the Alexandrians by surprise, before choosing a random person to kill, Glenn Rhee (Steven Yeun). Fans are just starting to get over the almost-death of Glenn, since we saw him fall into a zombie herd with Nicholas (Michael Traynor) in this season's third episode Thank You. For several episodes, Glenn's fate was unclear, but we found out in Heads Up that he managed to escape alive, as he began his journey back to Alexandria with Enid (Katelyn Nacon). Towards the end of the mid-season finale, Start To Finish, we saw both Glenn and Enid scaling a tree near one of the Alexandria walls, and in last week's mid-season finale, Glenn had another near-brush with death, trying to distract a herd of walkers so Maggie could escape from the watchtower.

It isn't known yet if the Season 6 finale will be Steven Yeun's last episode, but the introduction of Negan will certainly give the show a new dynamic. In the comics, Negan uses his group The Saviors to intimidate other communities such as the Hilltop Colony and The Kingdom into paying tribute to them, in exchange for The Saviors providing protection from the zombies. Negan's favorite weapon is a baseball bat wrapped in barbed wire, which he has dubbed Lucille, which is what he kills Glenn with in the comics. The big speculation is, now that Negan, or his back-up team, who may have been in this mysterious car, have seen Daryl take out the saviors, that the fan-favorite character will actually be the one to find himself on the recieving end of Negan's bat instead of Glenn. What do you think?