"Doctor?" Amy's voice wasn't particularly alarmed yet, more curious than anything. "What's this?" The TARDIS hummed around them, but one of the smaller screens that was normally was blank had fizzled to life and now blipped, numbers and characters flashed across the screen but she couldn't see any pattern to them. Occasionally a face would come into view but it was fuzzy and difficult to make out the details.
"This?" The Doctor was more interested in guiding the TARDIS than looking to see what Amy was getting at. "This is about to be the spaceship Guilderoy in the thirty-second century. It's the universes best traveling circus, they hop from planet to planet performing, it's utterly brilliant-"
"No, Doctor. Look! What is this?" The image grew stronger but was still unclear, the numbers started to come into focus so that she could read them as they zipped across the screen. She could also make some sense of the face, it was definitely a man. "And who is that?"
"Amy, you're missing this completely." He pointed up to the main screen. "Trapeze artists from Fae, using only their teeth. Tiger tamers who actually shape shift into the tigers. Shakespeare's plays, acted out in three hundred different languages, simultaneously. Roasted peanuts! Oh blimey, alright then, what have you got here?" He strode over, clearly disappointed that she wasn't interested in hearing about the circus.
"Oh." He said in a subdued tone, watching the screen flicker with numbers and symbols. The face appeared again and then disappeared in static.
"Well? Do you know who he is?" She watched the Doctor suspiciously now; he had made his face very carefully blank.
"Yes," He pulled the screen further out, a haunted look in his eyes. He pointed the sonic at the screen, an attempt to repair the signal she guessed. The image seemed to clear a little and she thought she could see a pattern in the numbers now, though they still meant nothing. "Well, that's interesting." He shook the sonic impatiently and scanned once more. The screen stopped its disruption completely and the image was now clear. The numbers looked like they might be tracking the minutes in the video, except there were many more than just the time that ticked by, she thought one might have been a set of dates.
"What is?" The Doctor continued to stare at the screen in a thoughtful way. "Oh just spit it out already, who is it?"
"It's, well." He finally leaned back from the screen and sighed. "It's me." The Doctor shrugged as though he had said nothing of consequence. He tucked the sonic back into his pocket and held his chin while he studied the numbers intently as they changed on the screen.
"What do you mean it's you? That's not you; he doesn't even look like you." Amy squinted at screen, he was much too lean to be her Doctor, and besides, he had sideburns, and no bow tie. The man in the image was looking in the direction of the screen but he wasn't looking into the camera, he focused on something small near the camera. His mouth was hinged half open, his gaze intense. His hair was shorter as well, and his face was harder. And then he looked into the camera and winked.
"Can he see us? Did he just wink at me? Doctor-"
But he waved off her concerns. "Just a recording." He said with a hollow voice. He turned to look at her then, a question in his gaze. "Pond, what have I told you about a time lord's regeneration?"
"Regeneration?" She asked him, wondering what it could have to do with the winking man on the screen. "Nothing, I suppose."
"Yes, I do have a rather bad habit of springing it on people at the last minute." He chided himself as he pressed more keys on the console and the image on the screen flickered and died. "When I die, Amy Pond, I don't truly die. I regenerate into a new form, new body, new personality, new teeth, all the accessories." He tilted the screen toward her then, the same man was on the screen, but it wasn't the image she had seen before. More men flickered across the screen, each just as different as the last. "I keep all the memories, all the information continues with me." He tapped his head with a sideways smirk and returned to the main console.
"You're going to die?" She asked as nonchalantly as she could. "Do you know when?"
"No actually, I have already died. Those men are not my future, they're my past." He said pointing to the small screen that continued to flash new images across it, there were many pictures, but they were the same men repeating, including the man in the video.
"But," Amy started, unsure of which argument she wanted to start first, "He doesn't look dead. And if he's your past, don't you remember what happened?"
"That is interesting isn't it? He looked very alive, and I remember, rather specifically, dying." He waved his hands in the air to signify the drama. "There were all sorts of explosions and fire. That's when I met you Amelia Pond," He grinned and ruffled her hair, much to her annoyance. "I crashed the TARDIS smack into your yard." He smiled fondly at the memory. "But I don't remember this, and I've never been there." He brought up the video onto the smaller screen again.
"What's there? How can you tell?"
"Those numbers, they're not just a time and date. They're a location. And they're telling me that it's Earth, in the 21st century, in South Greenwich."
"South Greenwich? What's that?"
"London. The suburbs," He said ominously.
"So you've never made it out to the burbs of London? How would you know?"
"Actually, I have been out there, they've a lovely picnic in the spring. I took first prize in the minced meat pie competition." He pulled on his suspenders importantly. Amy opened her mouth to argue but the Doctor pressed his finger against her lips. "But that isn't really South Greenwich." He tapped the screen. "That is parallel dimension South Greenwich. Somewhere I shouldn't be, somewhere I shouldn't even be able to go. That's what makes it so interesting." He pulled the lever of the TARDIS and they were traveling again, the floors shaking and bouncing as they went.
"Well, what is it then? Is he haunting you?" Amy waggled her fingers in as spooky a manner as she could.
"No, don't be silly, I'm much scarier in person." With one more twist of a dial, the TARDIS shuddered to a halt and they had clearly arrived at their destination.
"Well, what does he want in fake South Greenwich then?"
"It's not really a 'him' it's a 'me'. And it's not fake South Greenwich, Pond, it's parallel universe South Greenwich." He gazed at the numbers on the screen again. "I think I'm calling for help," He frowned. "Let's go find out, shall we?" He waggled his eyebrows excitedly.
"Why not?" Amy rolled her eyes.
"Are we at the circus already?" Rory emerged from below decks, drying his hair with a towel.
"Change of plans, dear." Amy grabbed Rory's hand as the Doctor disappeared through the door of the TARDIS. "Lose the towel; we're going to meet the ghost of Christmas past."