"Supernatural's" Robbie Thompson Cautions Dark Times Ahead for Winchester Bros.

"Carry on My Wayward Son" is more than just a classic rock song by Kansas for fans of The CW's "Supernatural." The song has been heard during the opening of each season's finale, played over a montage of the season's most significant scenes and events, a signifier that something big and epic is about to happen. In just a few months it will play once more, heralding the conclusion of "Supernatural's" tenth season.

Season 10 has been a change of pace for brothers Sam and Dean Winchester (Jared Padalecki and Jensen Ackles), battling the Mark of Cain, a mystical malady which threatens to turn Dean into a homicidal monster, instead of a powerful agent of evil. But in typical "Supernatural" fashion, along the way there have been some laughs, plenty of danger and heartbreaking reunions with old friends like Felicia Day's Charlie Bradbury.

RELATED: "Supernatural's" Robbie Thompson on Felicia Day and the Return of Charlie

With the series picking up steam as it heads toward the 10th season finale, writer Robbie Thompson spoke with us while discussing his recently debuted "Silk" series from Marvel Comics about the road the Winchester Brothers have walked so far, his full-time job of making their lives miserable, and the dark times that lie ahead for Sam and Dean.

Spinoff Online: Robbie, it feels like this season of "Supernatural" has been very different so far in that there's almost no real "big bad." There are villainous characters lurking in the background, but really the thrust of this season has been dealing with the magical malady afflicting Dean, the Mark of Cain. Is that a fair description?

Robbie Thompson: Early on in the season [co-showrunners and executive producers] Jeremy Carver and Bob Singer had talked about wanting to tell some more interior stories about the boys. I believe Jeremy has talked about this so I can share it as well. We're going to see a big bad present itself pretty soon here in our run. That big bad is going to be something that the boys and the people in their lives are going to have to wrestle with very soon.

The villains currently moving and plotting in the background are of course Crowley, the King of Hell, and his mother Rowena, a new character introduced this season. What do you feel actress Ruth Connell has brought to the show as Rowena?

Ruth is just a fantastic actress. She's a real treat to see in Dailies. She has great chemistry not only with Mark [Sheppard] who plays Crowley, but with our boys as well. I think she's added a fun dynamic and a fun way to sort of humanize Crowley and give some more insight into his character as well.

I don't believe you've had a chance to write Rowena yet, but I wanted to talk about the episodes you have written so far this season: "Fan Fiction" was the series' 200th episode, and "There's No Place Like Home" brought back Charlie Bradbury. Both were pretty big episodes with radically different tones. How did your approach change to write each of them?

That's a great question. That's one of the things I love about writing the show. One week you can write something as absurd as the musical and then the next you're dealing with a dark Charlie story. It's funny, when we finish this interview I'm going to hand in my last script of the year, and I was just thinking about this earlier. I started with a very, very light episode. You don't get much lighter than a musical episode of "Supernatural," and the one I'm handing in is really, really dark.

It's such a gift to get to write for this show when you have the dynamic that's set in this world with Sam and Dean as the anchors. Because they're such great actors they've given us such license to go in different directions. We can go as dark as we can and we can go as light as we can because those guys always anchor it in either direction. So it gives us permission to take some big swings. It's really a credit to them.

"No Place Like Home" brought back Charlie Bradbury, a character who has appeared a number of times on the show, and this season has also seen the Winchesters cross paths with characters they've encountered on earlier cases like Kate the werewolf. There are also some interesting characters who survived episodes and could perhaps return again later, like young Tina from the recent "About a Boy" episode. For a show that's been on as long as "Supernatural" is there a procedure for bringing back characters and having them become recurring players in the show? Any personal favorites you really want to bring back?

As far as a procedure goes, it doesn't matter if a character is alive or dead on our show. What does matter, though, is having a story. I tried for years to bring back Richard Spreight's character Gabriel, and I tried for years to bring back Rob Benedict's character, Chuck Shurley. There was always a question of can you find a story? Can you justify bringing back the character? That's always been the procedure.

I was lucky enough to get to write for Richard last year, and it was only one line for Rob, but it was probably the most fun one-liner I've written for the show, in the episode "Fan Fiction."

So if there's a character who has another story that is relevant to our boys, or to Castiel, or to Crowley, or the ongoing myth arc for the season there's a chance we can bring them back. And as far as bringing back characters? I always intended to write Cain who was played by Tim Omundson as a character that would come back, and by the time this comes out he'll have been back on the show in a great episode that Bob Berens wrote.

We've talked about what you've done so far let's look at what's coming next. You mentioned you're about to turn in your last script of the season. Other than that it's much darker than the musical episode, what can you tell us about it? Is it more of a mythology episode or a case of the week?

I have two episodes coming up. I really enjoyed writing both. One is more myth heavy and one is more case of the week. The case of the week episode is a personal story though. I'd love to say more than that, but I don't want to spoil anything. Or get fired.

As you mentioned earlier, dark times are coming the Winchester's way. I sort of got that vibe at the end of the episode that aired the week we're talking "Halt & Catch Fire." In that scene Dean talks about how he's found some peace and is just going to try and fight the Mark of Cain instead of searching for a cure. It does seem like every time the boys get a moment of peace it's your job as writers to disrupt that and make their lives a living hell.

Yeah, it's funny I always talk about how much I love Sam and Dean. And I do, but my full-time job is making their lives miserable. [Laughs] So I know it may seem like I don't love them, but I do. We're kind of like Lucy with the football in "Peanuts." You set things up so you can tear them all down again.To me it all boils down to our two brothers and the dynamic that happens between them and the people that circle them and make their lives both easier and complicated. I'd love to write an episode of the show where they just have a day off and they're doing laundry and binge watching "True Detective," but I've never gotten that episode approved. I did write one episode, though, where at least the whole point of it was for them to have 30 seconds off and that was the episode "LARP and the Real Girl."

That was a Charlie episode and there's a case, but really to me, that whole episode was about the boys getting into costume and LARPing for a day, at least it's implied for the day. We don't get to see the whole thing. That was my pitch for the episode. It was like, "Yes, there will be a case. And yes they'll intersect with Charlie again," but really it was about let's have them earn a day off where they can have some fun, drink some mead, and play with some foam swords.

It also felt like in the episode "Slumber Party," also with Charlie, you gave the boys a few moments of fun before everything blew up.

Yeah, and that's kind of our M.O. Moment of happiness and then sadness and pain, but that's "Supernatural." [Laughs]

How is it planning out the end of this season knowing the show has already been picked up for Season 11?

It's fantastic. We have such an amazing studio in Warner Bros. and an amazingly supportive network in The CW. Them giving us a pick up allows Jeremy and Bob to lay out the end of the season and then start making plans for the next season, and fingers crossed, more seasons to come.

"Supernatural" returns with a new episode Wednesday, March 18, 2015 on The CW.

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