Season 4 of Supernatural has been a powerful ride so far, shaking things up for Sam (Jared Padalecki) and Dean Winchester (Jensen Ackles). In addition to demons and angels, the brothers have to deal with Dean's lingering trauma from his time in hell and Sam exploring his demon-derived powers. Episode 4x13, "Afterschool Special," where Sam and Dean investigate a haunting at their old high school--and we got a glimpse of the boys as teenagers--drew some of the strongest numbers for the show since the season premiere. Season 4 has also picked up around one million more viewers compared to prior seasons.

Supervising Producer Sera Gamble recently dished to to TV Guide about what's up with the Bros. Winchester, answering fans' questions about the show and giving us a taste of what's behind season 4's secrets.

Warning: spoilers ahead!

Sera Gamble didn't give away too much, ducking a question on whether season 4 is leading up to a brother vs. brother confrontation. Among other topics, she did talk about older brother Dean's conflicted attitude towards Ruby, the demon who helped Sam while Dean was in hell. "He's unable to just see her in black-and-white anymore. She did too much for his brother." One fan worried about how much more emotionally broken Dean might become with his hell-related PTSD. "Dean's not some fragile guy walking through the world and having his self-esteem attacked," Gamble answered.
"He's a confident bad-ass who in private moments tends toward compulsively beating himself up. It's all internal."

She said "Vegas money is on yes" that we could see Sam interact in some way with his mother, Mary, who died when he was a baby. Mary has appeared on the show as a ghost, in an alternate reality, and in a time-travel episode but most of those encounters were Dean's. We'll also get "further insight into how Sam feels about his folks." Episode 21 will have an emphasis on Sam's internal landscape, what makes him tick. "I'm searching for a more intense word for 'intense,'" Gamble described the episode.

We'll also see more of Anna, Alastair, and Castiel. Series creator Eric Kripke will direct the season finale. Later this season, Sam and Dean find out about a series of books about...two demon-hunting brothers named Sam and Dean. Gamble says the ep is "dizzyingly meta," but that "the story eventually twists in an unexpected direction that's more grounded and substantial."

Supernatural airs Thursdays, 9/8 C on the CW.

Sources:
TV by the numbers
TV Guide - Sera Gamble Part 1
TV Guide - Sera Gamble Part 2