Supernatural season 10 spoilers
Supernatural Actors Misha collins(Castiel), Jensen Ackles(Dean Winchester), Jared Padalecki(Sam Winchester) and Mark Sheppard ( Crowley)Facebook/CW

Trouble road ahead for the Winchester Brothers!

Sam Winchester will have a hard time curing Demon Dean on the tenth installment of Supernatural because of the Mark of Cain. Supernatural Season 10 will find Sam and Castiel trying to figure out how to remove the Mark of Cain in order to heal and restore Dean back to normal.

Show runner Jeremy Carver explained to Entertainment Weekly why Sam will have difficulties in treating Dean.

"First, there is no demon possessing Dean. It was his own soul gone twisted. Moreover, the Mark of Cain served as a puzzle that needed to be solved.There are some added dimensions in terms of levels of difficulty," he said.

First and foremost, the boys will be worried about the Mark.

"It's still around, and it's very much a question for the first run of episodes if it still has an effect on Dean or not. And it's very much on the boys' minds as they plot out a game plan for the next batch of episodes after Dean is healed. In other words, the boys are very much focused on healing their relationship and healing one another." Carver said.

Carver also revealed that there is another person who is looking for Dean. Cole, a hunter but not a traditonal one, is someone from Dean's past, and is looking for him for different reasons.

Carver said, "He's a guy that has a terrific amount of hunting skills, but he's not a hunter in our sense of the word. He has no idea that the monster world exists, so imagine his surprise when he comes across the man he's been hunting and he is something other than human. He's a pretty cool character."

The casting details of the character Cole isn't revealed yet.

Jeremy Carver also teased that the Supernatural writers have talked about the possibility of bringing in Cain's brother, Abel, in Season 10.

"That's a great idea, and [it] has been bandied about in the writer's room," Carver shared.

Meanwhile, British actor Mark Sheppard, 50, who plays the demon Crowley on the paranormal drama series, is promoted to a series regular for the show's 10th season, reported The Straits Times.

Crowley and Dean to come closer in Season 10
Crowley and Dean to come closer in Season 10Facebook/CW

At the end of Season 9, Crowley was at Dean's side when he woke up, even as Sam was trying to summon the King of Hell to save his brother.

Mark Sheppard teased, "so what does Crowley want now? "Who knows? You'll find out, though,"

"You always find out," he told Examinar.com.

So, Crowley and Dean will be demon buddies in next season? We will have to wait and see.

Supernatural season 10 premieres today on 7 Octber at 9 pm on the CW.