A/N: Quick updates because of the snafu on the previous one ;)

"Geez, Doc, what do you do when you're not trying to impress someone?"

The Doctor grinned wildly as he stepped backwards out of the TARDIS so he could watch the expressions on his companions' faces. This was the best part. This was always the best part. This was why he traveled with friends. The look of awe.

The universe was wonder and hope and terror all wrapped up in a bow waiting for someone to tear it open and find out what was inside, like a cosmic Christmas morning every time he walked out the doors of the TARDIS. And sharing that feeling with others was what made Christmas. Or what made exploration. Or... he'd lost track of the metaphor somewhere but the point was that the universe was amazing and he loved to see people realize it.

He'd asked the TARDIS to find something memorable, something that, if no logical arguments would appeal to the Winchesters, would have to be enough to get them hooked. He had seen it when they were boys and could see it now: they both had the itch, the unstoppable urge to keep moving, keep finding the next adventure. And they could do better for an adventure than transdimensional beings claiming to be angels and demons.

So, the TARDIS has taken them to the planet Demeter, a planet whose orbit around its sun lined up with its planetary rotation so that one side was in perpetual darkness and the other in perpetual light. The side facing the sun was a popular tourist destination, full of leisure palaces with pools and people working on tans. But the dark side was just as breathtaking.

"They call it Demeter," the Doctor explained. "One side for winter and one side for summer."

Both of the Winchesters nodded, though they weren't looking around the planet or its perfectly-formed ice mountains. They were looking up at the sky, and for good reason.

The Doctor's grin got somehow wider as he followed their gaze, his hands in his pockets. All four of them stared up at the nebula above their heads, shining brilliant blues and purples across the perpetual night sky. The complete lack of light pollution meant the nebula looked even closer than it actually was. And every star in the sky looked slightly violet because of how purple the sky was.

"Persephone's Nebula," the Doctor said, still looking up at it alongside the others. "Demeter is always looking up at her daughter, never touching her in her winter of longing."

"Poetic," Sam said without looking away from the light show in the sky. Even someone who had come determined not to change his mind had to stop and stare at the wonder of the infinite.

The Doctor smiled and looked around at his companions. The Winchesters were a matched set, with quiet grins and their hands in their pockets, while Donna was louder about her grin as she hit the Doctor with the back of her hand as if to tell him he wasn't as impressive as what she could see. She kept him on his toes that way. Yes, she had the same awe that he loved to see, but she reminded him that he wasn't part of the universe's majesty.

And yes, sometimes he needed that reminder.

"Seriously," Dean breathed out, "is it like this every time?"

"Yes," Donna put in, grinning. "Yes, it is. And then there's lots of running, too."

"That's the fun part," Dean pointed out.

"Of course you'd think so," Donna laughed.

"And you don't?" Dean challenged. "What made you start traveling with him, huh? You get that high when you save someone, right? When you've been through hell and come out the other side dragging someone else out of the flames too?" Something in Dean's expression had shifted, though the Doctor didn't think he was aware of it. "Because when you're not with him, you don't always get those better endings, right?"

Donna's expression fell as she watched Dean. "I don't think we're having the same conversation anymore," she said in a tone that the Doctor had only ever seen her use with Dean. Something about having helped raise him when he was too young to remember her well turned her softer.

Dean shrugged, trying to look careless. "Metaphor was wrong, that's all."

"Ooh, right. Demons and angels and all that." Donna made a face. "No thank you. Every time I run into one, including the spacey kind, he ends up moping for days." She gestured toward the Doctor, who scoffed and drew himself up.

"I don't mope."

"You do," Donna insisted. "You do, and then you try to find someplace exciting to take your mind off of things, and then we end up in Pompeii."

"Pompeii?" Sam repeated, finally joining the conversation and looking like he couldn't help but be interested in such a big part of history. "You took her to Pompeii?"

"In my defense, I was aiming for Rome."

"Aim was a little off there, Doc," Dean laughed.

"It always is," Donna said. "He only says he knows what he's doing. But really, he's just flinging himself around the universe in his big wooden box and hoping he sticks somewhere fun."

"Hey," the Doctor protested, "you just said that all our trips are as brilliant as this one." He gestured toward the view they'd all been enjoying just moments ago.

"And I also said that they involved a lot of running," Donna said, her eyes sparkling as she looked toward Dean. "Poor thing needs constant reassurance."

"It's a big job," Dean agreed, and his grin was so wide that the Doctor didn't have the heart to tell them to stop it. The Winchesters seemed to have lost so much of the light that the Doctor had seen in them when they were little boys, and that light only got dimmer with age. That was true of most humans, but with Dean and Sam, it was different. Distressing. So, yes, the Doctor was willing to be the pinata so long as some of that joy came back.

But while Dean was laughing easily, something else was going on just behind Sam's eyes. The Doctor wasn't sure what it was until Sam spoke up: "So you're not always one hundred percent sure where you'll end up. That fits what I've heard about you."

When the Doctor turned Sam's way, Dean spoke up in the protective-but-proud tone that the Doctor had heard even when they were kids. "That's Sam. Always doing research."

"For good reason," Sam pointed out, though he was still looking toward the Doctor. "And I'm getting pretty good at recognizing when something is all flash and temptation but no guarantees."

The Doctor nearly lost a step. "That's—that's not a fair comparison," he spluttered, unable to come up with a witty retort when he knew what Sam was referencing.

"Sure," Sam said flatly but without dropping the Doctor's gaze.

"Oh-kay," Dean said, stepping in between the two of them. "I think he gets the point, Sammy." Then, he turned to give the Doctor more of his attention. "He's not wrong, you know. You want to run away from the problem and hope you don't ever end up on Earth again where we'd be within reach of angels and demons—and hope that their influence doesn't spread beyond Earth. That's a lot to stake a retreat on."

The Doctor sighed and let his shoulders drop, disappointed but not entirely surprised by the boys' outlooks. "And the Winchesters don't know the meaning of retreat."

"Hey," Dean said, one finger pointed at the Doctor's chest. "We don't run from fights and leave other people to clean up the mess. These guys, these angels and demons, they'll do anything to get the fight they want. And if we're the ones they're after, that means we're the ones that can throw a monkey wrench right in the middle of their plans for the Apocalypse." He smiled grimly. "They picked the wrong family to mess with."

"A tactical retreat would be—"

"Doc," Dean cut in with a sharp look that told the Doctor exactly how closed the conversation was.

The Doctor sighed, then set his shoulders, all at once deciding that he wasn't going to fight them—this time. "Right then," he said, striding forward, "if we're here to sightsee, I say let's get a closer look."