Supernatural season 10 episode 18 is airing tonight and fans will be thrilled to know that Charlie is back and that she has what Sam and Dean have been looking for all this time. Unfortunately, while she may have the Book of the Damned with her, deadly problems surface that could even lead to her demise. What will Sam and Dean do to spare Charlie? Find out by tuning in on tonight's show at 9 p.m. on The CW. You may also simply watch Supernatural season 10 episode 18 online using the free online stream link found below.

Note: This feature contains major spoilers on the upcoming episode of 'Supernatural' Season 10. Kindly read at your own risk.

The Winchester siblings have been looking for the cure to get rid of the Mark of Cain completely, and this week's episode will give them some ray of hope amid the things that still bring them darkness. Charlie will be their key to where the Book of the Dead is located, but she will have trouble keeping it as a man named Jacob Styne will be claiming ownership of the book. Worse comes to worse, he is going to shoot Charlie. Can Sam and Dean spare Charlie's life? What is the real motive of Jacob Styne? Find out all of the answers by tuning in on The CW at 9 p.m. EST or by simply watching Supernatural season 10 episode 18 online through the free online stream link at the bottom.

Actor Jared Padalecki recently gushed about the show and Sam and Dean's struggle to locate the cure," he said. "Both of these guys are struggling with their demons, struggling with their past. I think we will see Sam get dark. I know we do a little bit this season that you haven't seen yet. So I think you'll see it from Sam and Dean both," Padalecki added. Watch Supernatural season 10 episode 18 stream using the free online stream link at the end of this post.

Misha Colins also opened up about his character and Metatron saying, "Metatron's introduction to humanity, basically the moment he is a human, he is shot in the leg, which is not the greatest human sensation, so he is experiencing kind of the underbelly of humanity right from the get-go." He then added, "And yet, in spite of that, he is so overwhelmed by his senses that he is kind of elated by the whole experience as well, which makes him into even more of a chatterbox than usual, which makes Cas hate him even more than usual. So it's a spiral of despair as far as Castiel is concerned. But he is definitely manhandling Metatron and not terribly sensitive to his human needs."

The official synopsis of Supernatural season 10 episode 18 reads: "Charlie calls Sam and Dean and tells them she found the Book of the Dead that could help remove the Mark of Cain. Unfortunately, a man who claims the book belongs to his family shoots her. Meanwhile, Castiel and Metatron take a road trip to find Castiel's grace, but the journey doesn't go as planned."

"Book of the Damned" is set to air this Tuesday night at 9 p.m. EST. Watch Supernatural season 10 episode 18 stream using this free online stream link here.