Authors' Note/Disclaimer/Spoilers: This is a joint effort between myself, WhatBecomesOfYou, and my good friend saraholic. We've been working on this for quite some time, and are finally ready to be posting it. We own none of the characters, sadly. They all belong to the people who own the rights to them.

Spoilers through season 5 of CSI: New York, early season 8 of CSI: Las Vegas, season 7 of CSI: Miami, and series 2 of Doctor Who. Spoilers are quite possible for anything up to these points. Warning: temporary major character death.

And last but not least, please comment with anything you have to say. We'd be more than happy to hear anything you have to offer.

The Doctor jolted up with almost too much vigor. "Wooooah. Not doing that again."

Rose promptly turned to face him, slightly concerned, "What's wrong?"

He just stared at her, deep in thought. "I...I don't know. It just feels as if something's wrong. Something so wrong that it can't be right."

"Generally implied by it being wrong, Doctor," Rose said with a laugh.

Suddenly, the TARDIS began to violently shake and red lights started flashing.

"Doctor! What's going on!?" Rose yelped.

"Hold on, Rose! I have a feeling that the TARDIS senses what I sensed as well!"

The TARDIS gradually stopped shaking and the flashing dulled to leave the TARDIS basked in a faint glow of red light that made both the Rose and the Doctor appear to be stained in blood. The silence seemed to be so deafening that it was about to burst their eardrums when suddenly the TARDIS started to chirp.

"What the-" Rose squeaked, but was never able to finish as the TARDIS began to speak.

"Exterior altered. Danger. Fabric of time endangered."

"That's right!" the Doctor exclaimed, "That is the feeling of a rift in time. I should've recognized it immediately. Rose, we need to go outside and see how drastic the change is."

They both made their way to the doors of the cleverly disguised phone booth they called the TARDIS, but were unprepared for what they saw when they opened them. When they had arrived, New York may not have been a paradise full of sparkling clean roads and the like, nor was the foliage perfectly green and trimmed, but the juxtaposition was far too drastic for the Doctor's liking.

"It-It's like it changed overnight. is that even possible?" Rose mumbled.

"Rose, this is what we call a flux in the time space continuum. One small change in the past can lead to a whole smorgasbord of changes in the future," the Doctor stated, looking out over the change.

"In English please?" Rose asked, blushing furiously.

"In plain terms, the butterfly effect. Kill one butterfly in the past-"

"-and in the future, New York City becomes gloom and doom?"

"Pretty much."

"So we're looking for a butterfly murderer?" Rose asked, slightly confused.

"Not really. See, the butterfly effect goes far beyond simply killing butterflies. This is definitely going to necessitate the use of the TARDIS to get the information we need. And we better work fast because no one knows how long the world can survive in this state," the Doctor gestured to the city.

Buildings were crumbled. Streets were littered with drugs and homeless people. Worst of all, there was an absolute lack of plant life. Everything seemed to be dead. Rose felt something hit her arm and yelped in pain. When she looked down, she saw a drop of moisture on her arm quickly dissipate into a red mark.

"Acid rain," the Doctor remarked. "We better get inside the TARDIS quickly."

They both rushed into the TARDIS and shut the doors. The Doctor marched over to the central console on the TARDIS and got to work immediately searching for the answers to the current situation.

"Voice Command Sequence Activated," the TARDIS said, with a dreary monotone.

"TARDIS dear, search for any deaths within the past thousand years in New York City within the universe before this rift in time and then cross-reference with a search of any death within the past thousand years in New York City within the current universe. Report any differences," the Doctor rattled off.

"What do we do until then?" Rose questioned.

"Wait patiently and pray that New York City holds up until we get our-" the Doctor said, before being interrupted.

"One result found," the TARDIS stated.

"Who is the lucky person?" the Doctor asked, his interest piqued.

"One Lindsay Monroe, a crime scene investigator in New York in the year 2008." the TARDIS finished.

"Perfect!" he exclaimed, "Let's go fix this situation."

He fired up the TARDIS and took them back to 2008. They landed in the middle of a cheery and still very green Central Park. Once they got outside, they inhaled deeply; clearly very excited about the new intake of fresh air, in stark contrast to the heavily polluted air they experienced in the future New York.

"And we're here. Let's head over to the crime lab to try and save Miss Monroe," the Doctor said.

"It's a little late Doctor," Rose said, pointing behind him to where a small group of CSIs were crowded around a body. "If my instincts are correct, we've stumbled upon her a couple hours too late."