He didn't know what had tempted him to go to the near-future which was practically the sole domain of that isolated bunch who tended to keep themselves to themselves, but he had. As he was standing outside a bank where he'd been forced to jump through several hoops in order to withdraw money from an expense account the Brigadier had set up for him which was still in existence, his Tenth self ran past, dropping something out of his pocket as he did so.

Curious, he walked over to pick it up. Upon spotting another figure who was on a heading to do the same, he sped up. The other did the same. Both their hands met over the object.

"Oh, no you don't!" the small man in the shabby clothing exclaimed. "I saw it first."

"No, I saw it first!" he countered.

The smaller man replied by scratching his hand and snatching the long cylindrical object off of the ground while he pulled his hand back in order to avoid further injury. He gave the small man a venomous glare as he nursed his injury. The small man who he had once been completely ignored this in favor of examining his prize however.

"Give it here," he said as he made a move for the object. "You'll just play with it until you break it."

After a bit of wrestling with his former self who fought like a weasel, he ended the fight by finally snatching the object out of his former self's hand and holding it over his head out of the smaller man's reach. The little guy looked tempted to get the last word in by punching him somewhere sensitive, but apparently decided it wouldn't be worth it since he would be the one feeling it in a couple centuries' time.

"Hmm, it's got a psychic interface which I am blocked out of." he said as he made a study of the object which he continued to hold aloft out of the reach of his younger self who was trying to climb him like a monkey would a tree in order to get.

Moments after his younger self had gotten his hand on the object which he resolutely continued to hold onto, he felt something slip past the block in the psychic interface. Of the two of them, his younger self was paradoxically the better hacker, but then again, his mind was made for other things and he hated computers. Practically the instant after his younger self had slipped past the block, the object emitted a familiar sound, revealing its true function. Apparently, despite the fancy light on the end that would be useful in the dark, it was just another Sonic Screwdriver.

As the Sonic Screwdriver emitted the tone of a setting he wasn't familiar with, the ATM belonging to the nearby bank started spewing out money as if it were confetti. Seeing this, he quickly dropped the screwdriver. He and his younger self who'd climbed down when he realized that they hadn't found anything interesting both turned to look at each-other and both simultaneously yelled "Run!" before simultaneously turning to run off.

"Someone should put the world on alert." the Brigadier who'd been watching the show completely unnoticed by the Doctors said.

"For what sir?" the Lieutenant who'd accompanied him to the bank which had alerted him to the Doctor's presence asked.

"The apocalypse." he replied mock-seriously. "Those two actually agreed on something."

Rather than laughing at his feeble joke, the young Lieutenant paled and raced off. Five minutes later, alarms were echoing across London.

At the edges of the solar system, the leader of an invasion fleet turned to the captain of his flagship as rudimentary defense satellites armed themselves and turned away from Earth and asked "How the hell did they know we were coming?"