The Walking Dead invaded San Diego Comic-Con this year and, as usual, the cast and creative team brought the goods with them to Hall H. They debuted the first trailer for AMC's The Walking Dead Season 8. It is action-packed and full of everything fans could have hoped to see, but there is also something very mysterious being teased by the final shot in the trailer. What does it mean?

AMC didn't make fans wait as they debuted the trailer for The Walking Dead season 8 online right after it screened in Hall H at Comic-Con. It is a massive trailer, clocking in at more than 5 minutes in length. The first half takes us through all of the characters who have made it this far. Sort of a slow burn. Then it turns into a pure action montage, teasing the all out war that is about to bring Rick and Negan at one another's throats. It looks more like an expensive Hollywood action movie than a TV show for a large chunk of this trailer. But then comes that ending.

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Just when you think the trailer is over, we see a cane leaned up against a very clean room. The camera pans to some nice flowers in a vase on a nightstand next to a bed. Possibly a hospital bed. There is a man laying in the bed. He's either asleep or in a coma. Lots of grey hair. Long beard. Then he opens his eyes. It's Rick. And he has clearly aged a few years. Quite a few years. Wait, what?

With that, the trailer cuts out and we are left to wonder, what does The Walking Dead have in store for us in season 8? All we can do is speculate, since there is absolutely no context provided. What we do know is that this season is going to tackle the All Out War story line from the comics and that may be our best clue as to what is going on with Rick here.

Possible spoilers ahead for The Walking Dead, so read on at your own risk. After the All Out War storyline concludes in the comics, there is a two-year time jump. Granted, looking at old man Rick Grimes here, it looks like a hell of a lot more than two years, but still. There is a good chance that after the All Out War story rounds out The Walking Dead is going to do a little (or big) leap forward in the timeline.

There are other options though. Maybe this is just going to be part of a dream sequence that Rick is having? Maybe we are just going to see part of Rick's future in an episode or two? Or, God forbid, Rick wakes up and finds out that everything that happened was all in his mind and go all St. Elsewhere on us. That seems incredibly unlikely, but you never know. Either way, this one has us scratching our heads and the journey to figure this out could serve as a nice palate cleanser after The Walking Dead Season 7. Or this could wind up being really stupid. We honestly have no way of knowing right now.

We're going to have to wait a little while to sort this out. The Walking Dead Season 8 doesn't debut until October 22 on AMC, which gives us a few months to ponder this strange scene. For now, you can watch the trailer again for yourself and see if you can spot any hidden clues that may help the world figure this mystery out.