Supernatural‘s executive producer Jeremy Carver recently teased tonight’s mid-season finale, titled “Citizen Fang.”

“I think one of the hard things for Dean in this season has been how to reconcile being friends with a monster while his job basically entails killing monsters,” Carver says in this producer’s preview. “Dean realizes that Sam has been secretly keeping tabs on Benny and now suspects him of some gruesome murders.”

Making the situation more complicated is that Sam put Martin Creaser, who Carver describes as the “lovable, mentally unstable hunter we met a few seasons ago,” on Benny’s tail. Carver describes the episode as “pretty special” and says it packs “something of an emotional punch.”

Carver also recently discussed the episode with EW, teasing brotherly conflict, the cliffhanger, and some recent casting news.

According to Carver, in this episode, Dean “has to deal with the issue of what if Benny is not the type of guy that Dean can not trust any more. That’s sort of at the crux of the episode — is he or isn’t he?”

This is a question that “puts not only the brothers in conflict, but it puts Dean in conflict with Benny and the brothers in conflict with the other hunter, Martin. It turns out to be just a really, really emotional roller coaster of an episode.”

Carver says that “Dean wanting to believe the best in Benny is what drives Dean’s position in this episode,” but that Dean doesn’t have a choice as a hunter.

“He’s presented with a set of facts then he has to follow, even though he’s not so thrilled about it. I don’t think it’s that hard to get him to get into the car to go to the case; I think it’s what happens next where the complications ensue.”

Changing gears, in episode 8, Sam’s flashback revealed that Amelia’s husband was alive after all. That is a storyline that Carver says will continue in this episode: “The Sam-Amelia storyline sort of comes to a head in a few different ways with both in flashback and in present day.

“I can tell you that Benny is not the only present-day problem the boys are dealing with. I think Amelia factors into that as well and there are a few more surprises having to deal with all of this that are in the episode as well.” Carver says that “there are answers. And then more questions” about this story.

Like most of Supernatural‘s mid-season finales, “Citizen Fang” will end in a cliffhanger. “I think there’s some big-deal stuff that happens and it involves all the players that are in this episode,” Carver says of the ending.

“I think everything that started the season as a simmering conflict — whether it be Benny or Amelia — it all really rises to a boil here. I’m not going to say there’s tremendous, knock-down fisticuffs between the boys, but I do think there is some real emotional punching that’s done in this episode both in conversation and in deed.”

As for where the brothers will be heading in the second half of the season, Carver previews, “But I think the boys, coming back, are really going to need to find a way to decide, basically, what’s most important in their lives at this time. And that’s something I can promise is coming.”

Finally, on the casting of Gil McKinney as Henry Winchester, Sam and Dean’s paternal grandfather, for episode 12, Carver says, “When we have things coming up, we always want to have seeds we’re planting” in reference to episode eight’s multiple mentions of John Winchester.

“And also, we also make mentions of Mary — mom — in episodes coming up and part of that is the underlying reason for their quest is vengeance for what happened to their family.

“So any time we can keep family in the forefront of their minds — even if things aren’t really moving ahead on the actual quest — I think it keeps that kettle simmering at least.”