Takes place at some point during the 2005 series (probably before The Empty Child).
"That was amazing!" Rose exclaimed.
"I thought you might like it," the Doctor said, smiling broadly, as he manoeuvred the TARDIS through space and time.
"I still can't believe that's how they actually built the pyramids," she said, "It just seems so..."
"Yeah," she nodded.
"The cleverest ideas often are," the Doctor said, giving her a mischievous grin as he checked the TARDIS controls, "The hardest part, of course, was--"
He stopped talking and frowned, glaring at the console.
"What's the matter?" Rose asked.
"I'm picking up a radio signal," the Doctor replied, "but that shouldn't be possible."
Before Rose could say anything, the Doctor flipped a switch and faint music filled the console room.
"Yes," the Doctor said, looking troubled.
"Where's it coming from?"
"Somewhere in Spain," the Doctor said, glancing down at the console, "About 1550 CE, give or take."
"I don't understand," Rose said.
"Neither do I," the Doctor admitted, "There shouldn't be any radio signals on Earth at all during the 16th century, certainly not--"
"Bruce Springsteen," Rose said, as the music continued playing, "How can that be?"
"What say we find out?" the Doctor said, suddenly shifting emotional gears and breaking into his familiar manic grin.
The music faded in and out, getting stronger as the TARDIS approached its destination.
"This is definitely the place and time," the Doctor said, as the TARDIS materialised, "The signal is coming from somewhere nearby."
As they walked outside, Rose let out a small laugh. "I think the TARDIS was a little off again," she said, pointing to the paved surface beneath their feet.
"Not this time," the Doctor said, shaking his head. He knelt down and felt the ground. "Something is very wrong here."
After only a short distance, the tarmac abruptly gave way to dirt and grass. A little further along, they came to a crude wooden sign announcing that they were entering the town of Mallobo.
"Have you ever been here before?" Rose asked.
The Doctor shook his head no, and continued looking around, as if searching for something.
"The effect seems to diminish this way," the Doctor said.
"The anachronisms," the Doctor replied, "Like the paved area back there. Mostly small things, but still out of place for this time."
Rose looked around, but couldn't see anything that looked unusual.
The Doctor turned around and looked back towards the TARDIS. "I think this town is on the edge of it, whatever it is."
He started walking back the way they'd come, and Rose turned and followed him.
Once the passed the TARDIS, the anachronisms that the Doctor had referred to became much more obvious. There were ragged areas of cobblestone interconnected with random sections of concrete and in some places a kind of smooth metal that Rose wasn't familiar with.
The few people they encountered seemed completely oblivious to all of the strange things around them, and after seeing a man on a bicycle, Rose asked the Doctor about it.
"Whatever's happening is affecting them too," he answered, stopping to look at a bright red pillar-box, "As far as they're concerned everything's as it should be."
"It isn't though," Rose said.
"No," the Doctor said, "Not even close."
After a few more steps, Rose stopped, listening intently. "Do you hear that?" she asked.
It was the same song from the signal that the TARDIS had picked up, and from the sound of it, it was fairly close.
Looking around, the Doctor spotted a small boy, sitting beside the patchwork road, listening to what appeared to be a transistor radio.
"Could I see that please?" the Doctor asked.
"It's mine," the boy said, eyeing the Doctor suspiciously.
"I know," the Doctor said, smiling, "I just want to have a look at it. I'll give it right back."
The boy frowned slightly and then handed it over with a shrug.
As the Doctor reached for it, the Universe seemed to momentarily fold in on itself, and the radio had become a small digital music device.
The Doctor stumbled slightly, and Rose reached out and took his arm to steady him.
"What's happening?" Rose asked, alarmed.
"Time..." the Doctor said, "It's all wrong here."
"Hey," the boy said, tugging on the sleeve of the Doctor's jacket, "Can I have it back now?"
The Doctor absently handed him the device, and he happily resumed listening to the same song, unaware that anything had changed.
"We have to fix this," the Doctor said, "We have to find it, and fix it."
"We will," Rose assured him, still holding his arm, "YOU will."
"The further away from town they went, the fewer people they encountered, and the more bizarre the surroundings became.
"We have to find the focal point," the Doctor said, "The place where the effect is--"
Suddenly the Universe warped around them again, and a lorry, which had up until then been a cart, sped past them, blaring its horn.
Shortly beyond that, the terrain began to appear more normal again, mostly grass and trees, with only the occasional item that was out-of-place.
"Somewhere between," the Doctor said faintly. Every shift seemed to be having a profound negative effect on him.
"What should I be looking for?" Rose asked, as they started back towards the TARDIS.
"A concentrated area of changes."
"Like around the TARDIS?"
The Doctor frowned, then shook away the sudden ugly thought. What was happening here clearly pre-dated their arrival. "Yes," he said.
"What about that?" Rose asked, pointing at a glass and metal building. Other than the odd wooden door, it appeared to be very modern, and was surrounded by a cluster of other items, all from different times and places.
"Well done," the Doctor said, smiling weakly.
When they got to the door, he suddenly stopped and stared.
"What's wrong?" Rose asked.
"It can't be," the Doctor said, "I'm the only one. I know I'm the only one left."
"Can't be what?"
"It can't be what it looks like," the Doctor said, "what it FEELS like." He shook his head stubbornly. "There's no way this is a TARDIS."
Rose said nothing, just watched as the Doctor stood there so uncharacteristically indecisive.
After a moment, his expression turned to stone, and he reached out and opened the door.
It certainly looked like the TARDIS, at least somewhat, only dark and eerily silent. The console, which bore only a rudimentary resemblance to the one Rose was familiar with, was lying at an odd angle, and the room was littered with unrecognisable electronic components.
"Is it a TARDIS?" she asked.
The Doctor nodded.
"Does that mean there's..."
"Another Time Lord?" the Doctor asked, "No. It looks to have been deserted for a very long time. There's no one else." His voice sounded sad and distant.
"What do you think happened?"
"Probably crashed here," he replied, walking over and touching the broken console, almost lovingly, "Poor thing's been alone for who knows how long." He squatted down and looked underneath the console. "And now she's started leaking time."
The Doctor nodded, showing no sign of his usual excitement or curiosity. "It's probably been going on for a while now, but from the look of things out there, I'd say it's recently become much worse."
"Can you fix it?"
"I don't know..." the Doctor said, reaching out to touch the console again, "I can try."
He sat down next to the console and began carefully removing components with his sonic screwdriver and placing them gently on the floor beside him. No matter how obviously burned-out something was, he treated it with the same care, almost as if he were performing surgery, rather than making repairs.
Almost an hour later, he stopped and called Rose's name.
"I need you to get something for me," he said, "Something from the TARDIS. Can you do that for me?" He seemed so emotionally faded, so unlike himself, and it was difficult seeing him like that.
"Yes," she said, "Of course."
"Just past the wardrobe is a supply room. On a shelf you'll find a small box, about this big." He held up his hand, finger and thumb apart. "It's a sort of grey-green colour. I need you to bring it to me."
Rose nodded, and went back outside.
Whatever was happening was clearly getting worse. During the short trip back to the TARDIS, there were four more time-shifts, as trees became utility poles and the world re-made itself around her.
Fortunately, they didn't seem to happen inside either TARDIS, so hopefully the Doctor was no longer being affected by them.
She found the item the Doctor had asked for, and headed back to the other TARDIS, experiencing seven more shifts on the way there.
As she reached for the door, Rose looked at the strange building that was actually a TARDIS. Why didn't it look like a police box, like the Doctor's did? This certainly wasn't the time to ask him, but she filed the question away for later.
"It's getting worse," she said, as she handed him the small box.
"I know," he said.
The Doctor worked on the console for several more minutes before dropping his sonic screwdriver to the floor, and leaning forward, his head against the console. "I can't do it," he said, "I just can't fix it. It's too badly damaged."
"Is there nothing we can do?" she asked.
"There's one thing," he said, looking up. Rose had never seen his eyes so full of pain before.
Even though he hadn't said, she knew what that one thing had to be. The last remaining link to his people, other than his own TARDIS, and his only option was to destroy it.
Rose reached out and touched his hand.
"There's no other choice really," he said, gently squeezing her hand.
He carefully replaced all of the components he'd removed and then inserted the small box into the underside of the console.
"I'm sorry," he said, whispering to the console, as he set several switches, "I just need you to do this one last thing."
The Doctor stood up and looked down at the crumbling console.
"When I say run, run..." he muttered softly.
"Go!" he said, flipping the last switch and running for the door.
Once they were outside, Rose heard the familiar grinding noise, only slower and weaker, and then the door vanished from the side of the building.
"It's gone?" she asked.
"It's gone," he said, "Everything should start reverting back to normal now."
"Where did it go?" she asked, as they walked back to the TARDIS.
"To the end of time..." the Doctor said, taking her hand again, "With the rest of them."