'Supernatural' fans well know that the long-running CW series focuses as much on the angels, demons and monsters as the relationship between Sam and Dean Winchester, and season 9 will be no different. Despite the apparent peace between the brothers forged in season 8 finale "Sacrifice," it seems another major rift between Sam and Dean is set to blow the ninth year wide open!

Via TVLine, it seems there may have been more to Sam's near "Sacrifice" than we might have seen, as season 9 of 'Supernatural' will see Dean keeping a significant secret from his younger brother that threatens to tear the relationship a new one. Describing it as “one of the bigger issues of the series” and “a massive wrench” in the dynamic, series star Jensen Ackles previewed the latest Winchester conflict thusly:

They’ve got angels, they’ve got demons and all the other stuff in between to now deal with. They’ve got to figure out how to navigate the terrain with all the new elements. They’re really going to need each other more than ever at this point, and they’re going to have to rely on each other more than ever, which is going to be difficult because there’s a secret that Dean is harboring right now from Sam.

Ackles' co-star Jared Padalecki would only offer that the secret "heavily involves Sam,” and "has a lot to do with why Sam’s still alive,” so what might we have missed from the previous season finale? Could Dean's persuasion of Sam to forgo the trials, or his advice to let the angelic energy dissipate have come from a more sinister source?

Meanwhile, ‘Supernatural’ season 9 will feature the return of longtime series star Jim Beaver would return as his character Bobby Singer in an unknown capacity, while Felicia Day‘s Charlie Bradbury has been announced to pop up as well. Executive producers Jeremy Carver and Robert Singer (the real one) also recently previewed the CW drama’s ninth year, particularly the expanded role angels would play in the mythology going forward.

Well, what say you? Are you intrigued to see what new conflict divides the Winchester brothers in 'Supernatural' season 9 or would you rather the boys bury the hatchet already? Watch the latest Comic-Con recap below, and give us your predictions in the comments!

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