"Fine. When did you last see him?"
"It was in May, we were in the bunker, when he-he was dead, from fighting Metatron. I lay him out on his bed, and went to summon Crowley. I came back to his room and—he was gone. Just—just gone."
"Well, that's quite odd. Tell me more. Who is this you were fighting, and who is Crowley to you, exactly?"
Sam sighed. "Metatron. He's an angel who….ugh. This is going to take a while. I don't….I don't have time for this."
"You do realize I'm telephatic, Sam?" The Doctor asked.
"Oh, hell no," Sam said, cringing.
"Whatever's the matter?" He had a concerned tone.
"I….No. Last time…well, just, no. I can't do that again. I'd be useless to find him." He clenched his fists.
"Do what again?"
"Last time I had telepathy, I was turning myself into a demon. I can't do that again. I have to stay human this time."
"I understand that whatever happened to you last time was awful, but rest assured, my form of telepathy is nothing like that whatsoever. I'll try to be delicate, my consciousness is infinitely large compared to a human's, but I believe we can do this fairly easily. I will mostly be looking at your memories, but you may find some of mine seep into your consciousness in return. Take my hands."
Sam looked at the Doctor's outstretched hands, hesitating momentarily before taking them. "Fine. But…just…get it over with." He braced for what the onslaught, but found his mind floating off into an abyss of incredible sights. A star turned into a supernova before his eyes, nebulas explosively spawned new stars, galaxies whirled by, strange creatures spoke, metallic dome-like creatures screamed, legions of robots advanced, a blond woman stood with him on a beach, hugging him, dinosaurs roamed, countless humans stood in moments of defeat and victory, another woman with curly hair smiled at him cheekily, civilizations rose and fell, and— he felt something jerk him back, back toward reality.
He shook his head, squeezing his eyes shut and opening them again a few times as he adjusted to the shock.
"Sam?" The Doctor said.
"Wh-what? That was incredible." His voice was filled with wonder.
"Yes, I know. As I said before, my mind is quite expansive. I've seen much of my universe and some of the next. But your problem with your brother, I believe we need to address that."
"Yeah." Sam grunted, the grim resolve returning to him as the mental expanse of fantastical wonders faded. "I have to find him."
"What would you like to do?" The Doctor smiled, an infinitely old, knowing smile.
"You'd said we can't cross our own timelines. But we can do anything else, yeah?"
"Within reason," The Doctor replied.
"Is there a way we could track him?" Sam asked.
"Perhaps. The Tardis is psychic. If I could find a way to project your consciousness into her navigation controls, she might be able to zero in on his position in the presence via her tracking and psychic link systems."
"Her what?"
"May I show you?" He extended his hands again, which Sam took.
"Fine."
He saw the interior of the Tardis; there appeared a disheveled woman in a blue ragged dress, smiling, nodding, fading, whispering something to him. There was the same blond woman as before, her eyes glowing, a strange dome-like creature turning to dust, she kissed him and power surged through, burning, so that he could feel destroying every cell in his body, yet everything all at once sat in his mind, the infinite posiblities, the totality of all universes, the sum of everything that ever was, ever would or could be, and everything that must not be—he felt the same tug, and reality returned to his senses.
"Do you understand now?" The Doctor asked.
"I think so. It—the Tardis—she—she's alive. She's locked inside that…machine…thing. In that blue box. You're saying you could set up a way for me to communicate with her, and she could use….whatever that is….that…infiniteness she sees to find Dean."
"Precisely," The Doctor replied, smiling.
"You can do that, though?"
"I believe so." He nodded. "That infinite potential I showed you is called the Untempred Schism. It lies at the heart of the Tardis. She travels through it, taking me where I need to go."
"So…you don't…just fly her like a plane or whatever?"
"No. She's conscious, living. I travel with her as much as in her. Sometimes she takes me places else I didn't mean to go, but where I needed to. She just knows."
"Who was the woman I saw?"
"Which woman?"
"The blond woman who kissed you-me-you know. With the glowing eyes."
"She looked into the heart of the Tardis. Her name was Rose—but it—that's not important. We have work to do, don't we?" He motioned toward the police box, smirking ever so slightly as he snapped his fingers. The doors swung open and they entered.
"Well, that didn't take too long," Canton called from where he sat before the center console.
"No, it didn't," Sam said. "Look, sorry about that earlier. I can't be too careful with who I'm fighting."
"Ah, it's not a problem. I'd have done the same if I was fighting something as dangerous as whatever you are dealing with," Canton returned. "So, what's the deal? Are you traveling with us now?"
"Yes, I'm afraid we've had a slight change of plans," The Doctor said, stepping up toward the console, flicking a few switches. "Sam needs our help at the moment. I hope you don't mind the side trip."
"Wherever we go's alright by me," Canton nodded.
"Brilliant. Right then," The Doctor said, going down a set of steps toward a hallway.
"Wait," Sam called.
"What?" He asked, turning to wait a moment.
"Where are you going?! I thought you were going to hook me up to the ship's consciousness."