Warning: The following contains possible spoilers for season six of "The Walking Dead."

AMC's smash hit show "The Walking Dead" may bring back two deceased characters for the upcoming sixth season.

The Spoiling Dead Fans, a fan source that tracks rumors and spoilers, reports that actors Tyler James Williams (Noah) and Michael Rooker (Merle Dixon) were spotted on, or around, "The Walking Dead" season six set. At least one of them was reported to be in the filming area.

The unconfirmed information suggests that Rooker was in costume for Merle and that Williams was only seen hanging out in the vicinity of the set. Regardless, this development hints at a number of possibilities.

For starters, "The Walking Dead" has used deceased or long-missing characters in flashback scenes and hallucinatory visions in the past. Rooker himself was a part of one when he appeared to a delirious Daryl Dixon, played by Norman Reedus. So it's entirely possible that the actors were there just to film a quick cameo. If so, it will be interesting to see which currently alive characters they appear to and how their returns fit into the overall story.

Piggybacking off that last point: why is a flashback scene important?. Last season, dead characters appeared to Tyreese during his death scene. One theory is that showrunner Scott M. Gimple will use a similar tactic for killing off existing protagonists such as Glenn, Daryl or even Morgan.

However, before you start blogging your displeasure with the creative choices, The Spoiling Dead Fans are quick to remind you that the sightings are "still a big maybe." Nothing has been confirmed. However, the return of Noah and Merle would fit into Gimple's previously expressed view of season six.

Back at San Diego Comic-Con in July, Gimple mentioned that flashback scenes will be a crucial role in the first half of the season. Certain cast members have echoed this statement in recent comments, hinting at big time jumps in season six. Additionally, there will be an entire flashback episode this season. It's likely that Williams and Rooker returned to film scenes that take place in those flashbacks and time jumps.

Season six of "The Walking Dead" will debut on Oct. 11.