Supernatural co-showrunner Andrew Dabb has teased which characters we can expect to see make a return to the series before it ends its lengthy run, including a character who hasn't been seen in 11 years.

While revealing there are no plans to bring back the Ghostfacers, Dabb told TVLine, “I think we’ll definitely see some of the Wayward [Sisters] crew. At least one [character] we haven’t seen for 11 years [will return]. So I think there’ll be some surprises from the past and present of the show.”

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Supernatural has had a lot of characters come and go over the years, so the mystery guest could be anyone -- well, almost anyone. Adam is apparently not in the running, while Dabb said the Ghostfacers have yet been included in the mix -- though he admitted they weren't off the table.

Last season saw a number of familiar faces come back, most notably John Winchester and Chuck. And with the world once again facing the end times --and the show itself going out with a bang -- we know a lot more friends and enemies will pop back up.

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Episode 2 featured several cameos, setting the stage for the remainder of the final season. It's anyone's guess as to who will return, but the cross-country nature of the series means there are plenty of possibilities from over the years.

Airing Thursdays at 8 p.m. ET/PT on The CW, the final season of Supernatural stars Jensen Ackles, Jared Padalecki, Misha Collins, and Alexander Calvert.