It's all AU.

The Doctor spun around in a circle in the lobby, looking more startled then anything else, "Fantastic."

He spotted the familiar figure in black, walking down the street, headed roughly in his direction.

When he did he switched off the external monitors and slipped out of the TARDIS and leaned against the corner of his time machine and waited. When the Master was within reach he reached out, grabbed a handful of cloak and hauled him inside, with a surprising amount of strength and determination.

"Hello," he said, geninally, while he shoved the Master into a wall and yanked the doors closed behind them.

He eyed the Doctor for several long moments, thinking about the warning he'd gotten. Then he shrugged, walked up to him, grabbed him by the lapels of his coat, and stuck his tongue half-way down his throat.

Easiest way in the world to figure out what was going on.

Well. To Jack.