SHOUTOUT TO LADYDUNLA FOR LETTING ME KNOW MY POST-PARDUM BRAIN PUT THIS CHAPTER ON THE WRONG STORY. FIXED IT NOW.

A/N: So, I had this whole rant about how I don't appreciate getting swearing in my inbox over shipping when I'm writing a story that is NOT a romance and that acknowledges multiple ships, including but not limited to Dean flirting with every single one of the Doctor's companions and sleeping with River Song and has Donna seeing an interest in Cas because, let's be frank, lots of people see it and I'm gonna acknowledge that the same way I'm playing with every other possible ship… but then I got some very nice reviews and had a baby, and it's just not worth hijacking my chapter to tell the crazies to step back. I'll just say that I'm not here for shipping wars in a story that I've put literally years into. Doesn't make me want to take time away from my newborn to write, y'know?

*sigh*

Anyway…

As soon as Sam saw the big blue police box on the horizon, he started to shake his head, though he didn't say anything until he had caught up to Dean and shoved his brother in the shoulder. "I should have known you'd find trouble as soon as I turned my back."

"Yes, because of the two of us, I'm the high-maintenance one," Dean shot right back, shoving Sam at the shoulder as well. "You look like crap, by the way."

"That's what happens when your brother ditches you in the middle of a hunt."

"That doesn't sound like something I'd do."

"Sure."

Dean smirked, but now that they'd gotten the hellos more or less out of the way, Sam could see the shift in his brother as he tipped his head toward the Doctor and Donna, who were both grinning as they watched the two of them interacting. "So," Dean said, dropping his voice to something softer and more serious, "what do you think?"

"I think it's not the first time he's offered."

"I know."

"And I think if it was that simple, someone would have stepped in to keep us far away from the guy by now," Sam continued.

Dean raised an eyebrow and then pointed toward his own head. "Someone like an angel who erased my memories of the last time the Doc and I ran into angels?"

"Doesn't count," Sam said without missing a beat—he and Dean had already had this argument anyway, but it was easier to tease his brother than to discuss in front of the Doctor and Donna whether they'd stick around. If they did that, then their audience would try to have input, and the Winchester brothers didn't make decisions for anybody but themselves.

"Sure, Sammy."

Sam smirked, then tipped his head toward the Doctor. "He's not going to take it well, you know."

"Neither is Donna."

"Yeah, your babysitter is protective," Sam teased.

"Kinda nice to have a sexy protective babysitter all my own when I'm old enough to do something about it, huh?" Dean said, grinning wider and wider with every single word.

"Seriously, Dean?"

"Like you weren't thinking it."

"I wasn't."

"Your loss, then."

Sam shook his head as he turned back to the Doctor and Donna, who were respectfully letting the two of them have their teasing conversation without trying to push them into a decision, even if the Doctor was bouncing on the balls of his feet, switching which foot he was putting the most weight on with every movement.

Sam wasn't sure how he felt about the Doctor's obvious nerves. On the one hand, it was nice to see him caring enough to not only make the offer of travel but put forth that kind of emotional energy. On the other, it was such a stark difference to the Doctor's response to Dean's deal with Hell that Sam didn't trust it. It didn't matter to him that Dean had come back; the Doctor had still refused to help them avoid his death in the first place.

Hell had changed Dean. There was no denying it. And while Sam was aware of all the changes he'd been through as he drifted closer and closer to Hell and his own destiny he was trying to fight, he wanted to shield his brother from what had happened. Dean had already been through enough; he shouldn't have been forced to suffer in Hell.

Before Sam had met an angel, he'd believed in a fair and just God, and he hadn't been able to reconcile that belief with what had happened to his big brother. Now, he didn't know what he believed anymore—but he knew he believed anyone who had stood aside to let Dean go to Hell didn't deserve his respect, let alone his friendship.

So, he didn't bother to censor himself as he asked the Doctor outright: "What changed?"

As expected, the Doctor stopped all motion and blinked at Sam a few times, obviously trying to place the question in context. "Mmm?" he asked at last, a sound that didn't acknowledge anything when he was waiting for Sam to lay out his cards.

Sam shook his head as he gestured to his brother. "You wouldn't help us before. You said everything was set in stone. And now you're parading around telling us we shouldn't be shoehorned into our destiny. Seems hypocritical."

The Doctor's shoulders fell. "I know it looks that way from the outside," he said gently, but Sam already didn't appreciate his tone.

"It doesn't just look that way."

The Doctor took a deep breath and let it out slowly. "I can see it," he explained, still using the same tone of voice that had Sam even more on edge than before. "I can see all the possibilities in Time. I can see what can be changed and what can't, which moments are fixed moments and which ones are fluid."

"That's crap." Sam crossed his arms as the Doctor raised an eyebrow. "It is. You really mean to tell me that my brother dying is a fixed point in time, but the end of the world isn't?"

To Sam's surprise, the Doctor drew himself up taller, his eyes flashing with the power that he always tried to contain but never quite managed. "Don't tell me a Winchester is admitting defeat to that feathery excuse for a supernatural being," the Doctor said, his voice soft but dangerous. "I've seen the end of the world, Sam Winchester, and it does not end because some powerful beings thought Earth would be the right playground for a turf war."

Before Sam could say anything, Dean cut in. "You know, that's actually comforting?" he said. "Kind of like concrete proof that we're right."

"But you just said that Time can be fluid," Sam pointed out. He'd had enough of false hopes to last him a lifetime; he wasn't going to believe that he could outrun the destiny the world was trying to shove into his hands just because the Doctor said it was possible.

"Yes, I did, and I see where you're going for this, but that's not the point of what I'm trying to tell you," the Doctor said, both eyebrows raised with his hands out in front of him, gesturing with nearly every word. "I saw the world being overtaken by your sun. It was the first da—Rose and I went together," the Doctor said, pausing just long enough that literally everyone could see the stricken expression on his face.

And yeah, Sam didn't like the Doctor. Didn't trust him as far as he could throw him. But if there was one thing that stayed consistent over everything he'd seen about the guy, everything he knew, it was this: the Doctor wouldn't invoke Rose's name for no good reason.

So, with a sigh, Sam let his shoulders drop and nodded almost imperceptibly. "Let's start with one trip. Just so we can hear you out. I'm not promising anything more."

The Doctor lit up with a grin and clapped his hands together. "Well then! Come on, boys and Donna—we've got the whole of Time to find something fun to do!"