There are only a couple of weeks to go until the season 13 premiere of "Supernatural," and fans cannot wait to delve into the world of Sam (Jared Padalecki) and Dean (Jensen Ackles) Winchester again as they fight off monsters, ghosts, and other supernatural beings.

The season 12 finale contained a lot of cliffhangers, with viewers having a ton of questions at the end. What happened to Castiel (Misha Collins) and Mary (Samantha Smith)? Did Crowley (Mark Sheppard) really die?

Unfortunately, the sad truth is that Crowley is really unlikely to return to the series. After the season finale, actor Mark Sheppard posted on Instagram that it was "time for something new," thanking all the production staff of "Supernatural." He also took to Twitter to confirm that his stint on the show is pretty much over, much to the disdain of his fans.

The loss of Mary Winchester was also quite a shocking turn for Sam and Dean. In the season 12 finale, after Crowley sacrificed his life to trap Lucifer (Mark Pellegrino) in an alternate dimension, the devil managed to stab Castiel in the back with an angel blade and dragged Mary to his fate before the void closed, leaving the Winchester brothers agape in horror.

It was a great loss for the Winchester brothers, but fans think Mary would come back in one way or another, as the show has a reputation of bringing back dead cast members. It remains to be seen in season 13 how Sam and Dean would cope without their mother, and if they are going to do something to get her back.

Meanwhile, Castiel's return to the show is also hugely debated. His death in the season 12 finale seems to be final, but according to a slip up from Padalecki himself, it looks like Castiel would indeed come back in the new season. In a convention in Rome, Padalecki carelessly mentioned the actor's name in one of his answers to the audience.

Talking about the anticipated "Scooby-Doo" episode of the upcoming season, Padalecki said: "We did all the dialogue. Jensen and Misha and I." The actor did not comment further about the slip-up.

Catch the season 13 premiere of "Supernatural" on Thursday, Oct. 12 at 8 p.m. EDT on The CW.