A/N: My first crossover. I chose E.R and Doctor Who and I checked the site and no one else has done one for these two shows so, it's different and I hope you enjoy it.

3 weeks ago:

"Doctor! Is Jack ready with that laser yet?" River called out over the rumbling inside the TARDIS. She placed her hand tightly on the control panel as she flipped a switch and pressed some buttons.

"... Any moment now, we just need to keep that meteor steady for a few more minutes!" The Doctor yelled trying to keep his balance from this bumpy ride in the TARDIS. "Hurry up... JACK!" The Doctor was concerned that there was no signal on the screen; he hoped that Jack was ready.

"All systems go." Jack smiled as the screen turned on. His eagerness was never his downfall. "Sorry about the delay, the computer was down. But, I'm here now." He added with his trademark grin.

"There you are, Jack! We're ready whenever you are." The Doctor called out over the noise.

"Firing in 3...2...1!" Jack pressed a few buttons on the console in front of him. He wasn't the slightest bit nervous.

As the countdown reached 1 an intense red laser beam shot out of Torchwood Tower and up to the top of the Earth's atmosphere where it struck the meteor that was heading towards the planet below.

"Did you destroy it?" River asked nearly losing her balance again.

"I surely hope he did... Otherwise the Earth is doomed." The Doctor mumbled.

A violent tremor rampaged through the TARDIS as the meteor was disintegrated and it sent both River and the Doctor stumbling to the floor... hard. Luckily, Jack had good aim and the laser didn't hit the TARDIS.

"Direct hit!" Jack cheered from the base. He was congratulating himself.

The Doctor and River were lying on the floor in silence but they were both okay. River sat up with a slight headache and she looked around for the Doctor who was already on his feet with a childish grin all across his face. She rose from the floor trying to regain her balance.

"We did it!" the Doctor beamed as he skipped over to River and gave her a massive hug. She was laughing at the Doctor's overall happiness and she was relieved that they stopped the meteor before it was too late. "Nicely done, Jack!" The Doctor said as he looked to the monitor with Jack on it.

"You too, Doctor and River." Jack smiled and saluted. "Look outside, it's a brilliant sight from down here, what about up there?"

The Doctor placed River down and ran to the doors and pulled them open. He peered outside with River standing next to him. All that was left of the meteor was a trail of glowing orange and green dust that floated calmly around in the Earth's atmosphere.

"It's... beautiful." River gasped.

The Doctor placed a hand around River's waist and pulled her close.

"We should go soon, before the media gets interested and spots us." The Doctor added.

"Yeah, the media does get harder and harder to keep away... Trust me! Well, until the next time, I'm outta here." Jack said changing the subject and he switched off the screen.

"We just saved the Earth, its over." River said. "...And that means... vacation?" she pleaded with a seductive voice. She was looking at the Doctor, her bright green eyes begging him to give in.

He turned his head and raised an eyebrow at her with a grin. He leaned close to her and planted a quick kiss on her lips. "Vacation!" he cheered as he stepped back and closed the doors. The excitement in his step back to the control panel had River's heart skip a beat.

She followed him to the controls and shone him a smile. "Where to?" she asked leaning over the panel next to the Doctor.

"Anywhere..." he looked up and returned the smile. "...As long as it is amazing."

The TARDIS began to fade away to wherever the Doctor and River felt like going and they were completely lost in happiness. However, there was something that they both missed...

The particles from the meteor were floating around space and eventually they will find their way into the Earth's atmosphere and the chemicals in the air would react with the alien particles and create something new, different and deadly...