Sam (Jared Padalecki) and Dean (Jensen Ackles) were back on their monster-of-the-week grind in Thursday's episode of Supernatural, "Atomic Monsters," which marked Jensen Ackles' sixth and final time in the director's chair for the CW series. Still reeling from Rowena's (Ruth Connell) huge sacrifice, the boys tried to regain a sense of normalcy by taking on the case of a dead cheerleader, whose body was left mutilated, and another who'd mysteriously disappeared. While Dean quickly bounced back from his brief existential crisis, it looked like Sam was on the cusp of his own downward spiral.

The younger Winchester had been holed up in his room for days mourning recent losses that include Jack (Alexander Calvert), his mother Mary (Samantha Smith), and Rowena. Plus, he'd been having recurring dreams about turning evil, which have kept him on edge. Sam's latest vision painted the clearest picture yet, with Dean confronting Sam after he'd slaughtered a dozen hunters, including Bobby (Jim Beaver) and Jody (Kim Rhodes). With demon blood coursing through his veins, Sam seemed to be at the point of no return in this nightmare, ignoring Dean's pleas to stop and then snapping his brother's neck without hesitation. Does this mean Sam is headed back to the dark side?

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Sam was really going through it, and in a heart-crushing moment at the end of the hour, opened up to Dean about how he's been feeling. Countless losses of friends and loved ones have made it all too much to bear, and for Sam, the weight of that grief is suffocating at times. Though he brushed it off in the end, hoping to feel better in the morning, Sam's confession in the Impala raised concerns for Dean, who was counting on his brother to be strong and fully present amid all this uncertainty.

"I think the state of his brother always worries Dean. That's who he fights for," Jensen Ackles told TV Guide. "When that support, that base strength in his life starts to waver and [he] starts to second guess himself, that will certainly affect Dean in a way of, 'I can't let him go down this road' or 'I need to figure out a way to help him out.' So it'll be a struggle, not against each other, but for each other. Sam is struggling to find a purpose and Dean is struggling to help Sam find purpose."

Jensen Ackles and Jared Padalecki, <em>Supernatural</em>Jensen Ackles and Jared Padalecki, Supernatural


Also experiencing a personal crisis was Chuck (Rob Benedict), having been weakened by Sam (who shot him with the Destroyer) and left stranded on Earth when Amara (Emily Swallow) refused to help him. The creator of the universe resurfaced in Thursday's episode to get a much-needed ego boost from his number one fan, Becky Rosen (Emily Perkins).

"I was super stoked," Ackles said of Becky's return. "The Chuck and Becky storyline quickly became my favorite part of the episode. From the director's chair, I quickly became just an audience member watching these two play."

Much to Chuck's surprise, Becky isn't the same obsessive, boundary-crossing fangirl who tricked Sam into marrying her in Season 7. She got married, had two kids, and carved out a nice, normal life for herself. It's refreshing to see Becky, who used to represent the worst of fandom, evolve and become a level-headed woman who's still passionate about the Winchesters, but expresses her enthusiasm in a much healthier way. She still writes fan fiction and even runs an Etsy shop selling unofficial Supernatural merchandise, but she also learned from her past wrongdoings and moved on. So when the ex-boyfriend who mistreated her showed up unannounced at her doorstep, she wasn't exactly receptive. Desperate and lonely, Chuck dialed up the emotional manipulation and convinced her to help him get his mojo back, so to speak. After some encouragement from Becky to write a story with higher stakes, Chuck crafted his perfect ending, which alluded to at least one Winchester death and left Becky (and us) distraught. "You can't do this to the fans," she pleaded. We're right there with you, sis.

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It's unclear which Winchester Chuck planned to kill off, but if it wound up being Sam, Ackles admitted he wasn't sure what Dean would do without his younger bro.

"That would have to be a bridge crossed when he came to it," Ackles said. "Right now, and for a long time, Sam's been the reason that Dean keeps fighting. If you take that away from him, then what does he have? Is there a will to keep going? I don't know how that would shape up from Dean's perspective. Maybe he finds something to fight for or maybe he finds somebody to fight with. Maybe he calls it quits."

Ackles might not know how Dean would carry on if Sam were to die, but he already knows the ending to Supernatural. The actor revealed that his reaction was not all that dissimilar to Becky's visceral response to Chuck's proposed finale.

"I will say Becky was a little more vocal about how she felt, and I felt very similar, but internalized it," Ackles explained. "When I was told of how they're going to wrap up the series, I took pause and I had a hard time digesting that situation. I've later realized that I'm just too close to the situation. I needed perspective. I needed to step back and look at it from an audience's perspective and think about how the ultimate ending would affect me. Then I kept coming back to the conclusion that this is actually wonderful."

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He continued: "I guess it's just that three letter word END that I was having such a hiccup with. And, as I think most of us feel, we just never thought it would come to that. We never thought it would end. And so, maybe it was just the notion that was giving me such a hiccup with it as opposed to how it actually comes to an end. But I think the how and the means are going to satisfy."

Jensen Ackles, <em>Supernatural</em>Jensen Ackles, Supernatural


The road to get to that ending will be long and arduous for Sam and Dean as Chuck tests them in ways they've never experienced before. "Atomic Monsters" teased stronger villains and a devastating fight, which is nothing new for the Winchesters, but for the first time in the show's 15-season run, we'll also see them facing smaller hiccups that will impede their efforts to fight the good fight.

"Chuck is now starting to kind of take away little aspects of their lives in a way that is a little unexpected. You think about the way those hero stories are told and they don't have time to sweat the small stuff. They don't have time to get a cold. They don't have time to go to the doctor and get a check-up. Then normal stuff starts happening to the Winchesters and that's exactly what they have to start doing," Ackles said.

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In addition to fighting monsters, it looks like Sam and Dean will also face everyday roadblocks, like the Impala getting a flat tire. "We start seeing Chuck slowly disable the Winchesters' mojo and it's heavy. It's hard for them to operate in that world because they're so not used to having to live in a normal world. Is it because Chuck has written them as the hero and so they don't deal with that kind of small stuff, or is it just then we just have never seen it?" Ackles added. "All of that cool is kind of gone now and they're trying to figure out how to deal in a world where they need that mojo. They need to be able to know that they can go up against a nest of vampires and be able to take out six or seven each, but if they can't even take out one, then that's gonna be a big problem."

Supernatural airs Thursdays at 8/7c on The CW.

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