A whirring noise filled the bullpen. Dr. Spencer Reid rolled his eyes and sighed when the TARDIS materialized beside his desk. He was definitely going to need to have a word with The Doctor about his entrances.

Ignoring his speechless, terrified co-workers, Reid opened the door of the TARDIS and stepped inside.

"Ah, Spencer, lovely to see you again." The Doctor was whizzing about the control room poking at random contraptions on the console. He pulled a lever, and it made a sound like a train whistle. The Doctor clapped his hands happily, "Where to, Boy Genius? A nice, relaxing swim in the lava pools of Calcan? A jaunt about the moon? Oh, maybe not, the moon is so cranky this time of year. But Jupiter, Jupiter is very amiable. Anyway, she owes me a favor. What do you say?"

"Doctor!" Reid was struggling to keep his cool. "In case you didn't notice, you just landed in the middle of the BAU!"

"Oh?" The Doctor raced to the door and peered out into the bullpen. He ducked back inside, shutting the door. "Oh. Well, that wasn't supposed to happen. I thought this was the library."

"The BAU doesn't have a library."

"And why not?" The Doctor whined. "Every building should have a good library."

The TARDIS door opened again. Hotch, Morgan, and Rossi stepped in, guns drawn and pointed at The Doctor.

"Let him go!" Morgan demanded.

"Oh dear," The Doctor looked to Reid, who hadn't moved from his side. "Did I do something wrong?"

"Guys, it's fine." Reid assured them. "This is The Doctor."

"What are you, Doctor? Some kind of..." Hotch glanced around the room, finally realizing that it was bigger than it should've been. "...alien?"

"I am a Timelord." The Doctor gave a curtsy. Reid smacked his arm. "And this is the TARDIS. Time And Relative Dimension In Space."

Morgan was the first to lower his weapon, "This is a nice trick, Reid. You'll have to tell me how you did it. Well done."

Reid shook his head, "It's not a trick, Morgan. It's all true. The TARDIS is a spaceship and a time machine. The Doctor is an alien, and he travels around and meddles in other people's business." The Doctor pointedly ignored Reid's glare.

"Some might call it 'saving the planet'."

"Is it really 'saving' it when most of the time you were the one who put it in danger in the first place?" Reid argued.

"I think so, yes."

"Reid." Hotch cut in before Reid could argue again. "How do you know him?"

"Well, when The Doctor goes on his adventures, he sometimes takes people with him."

"So...when you say you've got plans for the weekend, you mean you're traveling across time and space with an alien." Morgan commented. Reid nodded sheepishly. This was not how he wanted his team to find out about The Doctor. To be perfectly honest, they were never supposed to find out at all.

"What are these adventures?" Rossi asked, looking like he really didn't want to know the answer.

"Last week, Spencer and I saved a spaceship from being sucked into Earth's gravitational pull. Saving the planet from certain doom as well, if I might add. A few months ago we accidentally invented the high-five two hundred years early. We saved London from some confused nanogenes awhile back. Ooh, that could have been disasterous, especially considering it was during the London Blitz. Oh, and our first adventure together... Spencer, do you remember meeting Charles Dickens?" The Doctor smiled as he recounted his adventures with Reid.

While The Doctor talked, Reid couldn't help glancing at his team members. He watched as their eyes got wider and wider.

"Anyways," The Doctor said. "I was just picking up Spencer now. I'll bring him back in about five minutes. You'll have barely missed him."

"Wait, Reid." Morgan shifted his feet. "These adventures...are they dangerous? Is he dangerous?"

"Yes, Morgan." Reid answered honestly. "I've been injured before. I've even died. But I wouldn't miss it for anything."

Morgan nodded solemnly. Hotch and Rossi left the TARDIS, still half-convinced they were dreaming. Morgan hung back before saying, "You know, Pretty Boy, I've always wanted to meet the Wright Brothers."

"Kill Devil Hills, 1903, coming right up!" The Doctor flipped a switch, and they were off.

Author's Note- Continue or not?