Scully should have figured that this is how it would end, hurtling through space on a craft like she'd never seen before - probably because it wasn't from this Earth.

All life besides the two of them on board was dead, their guide having succumbed to an infection that had spread around the ship. It was a nasty illness - it started with a cough, which then spread to the victim's chest, until they were throwing up blood, their skin shrivelling up, pockmarked with big red pustules. It was a horrifying thing to watch. It had turned even Scully's iron stomach.

The source of the infection was a biochemical substance, released into the spacecraft by one of the extra-terrestrial beings that had been held inside, and that substance had reacted with the oxygen in the air, and the terrible plague had become airborne. The infection had flooded its way through compartment after compartment, infecting everyone on the ship until at last, Mulder and Scully had managed to seal themselves on the bridge of the ship, locking the contaminated air outside.

And so, Mulder and Scully stood, the only two people in the endless dark of space, staring down at their world below.

"You were right, Mulder," Scully said, staring transfixed down at the Earth.

In spite of everything, Mulder couldn't help but smile. "About what?"

"Extra-terrestrial life. Aliens. Goodness knows what else."

"Did you ever doubt me?"

Scully gave him a look.

Then she looked back out at the world outside. "You know, Mulder," she said, staring out into the inky blackness and the big, blue Earth, "in all my life, I don't think I've ever seen something quite as beautiful."

Mulder's eyes shifted over towards her, his mouth curling upwards as his fingers inched over towards her, his skin brushing hers. She turned and smiled at him, that one wide smile of hers that Mulder would have died to earn.

Then it faded as she looked back down towards Earth. "Everything's nicer from far away," she said. "Looking at it from up here, you almost wouldn't know about all the wars. All that hatred, and anger. All the people that would spill so much blood over such superficial things."

Mulder looked down at her quizzically and laced their fingers together. "Yes. But down there, there's also love. Compassion. Family. Hope."

"You've never been one to talk about hope."

His eyes flickered from her eyes down into her lap. "Scully, I-"

Whatever Mulder was about to say was interrupted by a loud crash, and then a loud alarm, as the room was flooded with a bright red light. He instinctively threw himself over Scully, shielding her from danger.

She pulled herself out from under him. "Mulder, what's happening?"

"I think the ship's crashing," Mulder said, hastily looking all around the bridge for something that would tell him what to do. All the LED screens were flashing a warning signal. He couldn't make any sense of the buttons on the dashboard. Damn it. "We're heading towards Earth."

Scully looked panicked for a moment, and then locked eyes with him. "Our guide. He mentioned the stabiliser. If we can hit that switch, maybe we can get the ship to settle, and we can guide ourselves down gently."

"We're not pilots, Scully, and even if we were—"

"Do you have a better idea?"

Mulder sighed. "Where's the switch?"

Scully pursed her lips and nodded out into the hallway. "Out there."

Without thinking, she started marching towards the door.

"Scully, don't—" Mulder grabbed her by the wrists— "if you go out there, you'll be killed."

"If I don't, this ship is going to crash into the Earth, and the entire planet will be infected. We can't let that happen."

"There has to be another way." Panic was clawing desperately at Mulder's heart, as he clutched onto Scully's wrists.

"We don't have time."

Mulder looked between the corridor, and Scully and back again. "Fine."

Then he did the last thing that Scully ever expected him to do, he pulled her close, his fingers curling around her cheek and tucking into her hair and kissed her fiercely. In shock, it took her few moments to realise what he was doing, and before she could stop him, he'd launched himself over into the airlock compartment that sealed the bridge from the hallway, and closed himself in.

She fled after him.

"Mulder, no," she said, desperately slamming her hands against the glass. "Don't open that door."

"Scully, there's still a chance that one of us can get out of this alive," he said. "It has to be you."

"I won't let you do this. I can't let you do this."

"You can. You have to," he said, his palms joining hers, separated by the glass.

"No. I won't," she said, tears spilling down her cheeks. "There's still so much you have to do, Mulder. People only you can beat. Let me go, instead."

Mulder smiled, mirthlessly. "I can't do that, Scully. There isn't an x-files without you. There isn't a me without you. Scully, there are so many things you need to do with your life, so many things you still can. There are so many people waiting for you back home - your mother. Your brothers. You can still be a doctor. You can still find a career for yourself; a family. Find yourself a good man. Settle down. Adopt a child. There is nothing waiting for me at home. The only thing I have in my life is you, and I'm not going to lose you."

"Mulder," she whispered, still weeping. "Please."

She bent her head against the glass, and Mulder joined her. Only one strip of glass separated them, but it felt like a whole universe between them.

"You have to live, Scully. You have to live and keep on living and bringing life into this world. That's how we beat them, that's how we beat their game. You have to live. Promise me you will."

"I can't." Scully's voice was barely there. "Open the door. Let me in."

Mulder smiled once more, a sad smile as tears began to trickle down his face. "Sorry. No can do."

Then he turned, and opened the airlock out into the infection flooded hallway.

"No," Scully howled, dropping to her knees.

A few moments of extreme turbulence went by, Scully barely holding onto the door handle as the floor shook. Then it was calm, the red light lifting up and the alarm fading. Mulder came shifting back later, pulling himself towards the door on his hands and knees, already covered in a sheen of sweat. He leaned against the glass door once more.

"Scully," he whispered, reaching out a hand and tracing her features with his finger.

"Open the door. Let me help you. Maybe I can—"

"No," Mulder said, firmly. "You'll get infected."

"You have to let me do something."

"Get yourself home. Live. Show that smoking son-of-a-bitch that he didn't win this game," he said.

"I don't want to do it without you," she said, "you said it yourself. There isn't a me without you."

"You'll manage," Mulder said, with a half smile. "You're Dana Scully."

Then he was racked with a coughing fit, blood spilling from his mouth and dribbling down his chin.

"Mulder, please," Scully begged, her heart breaking in two. "Open this door."

"Not a chance."

He was starting to wheeze.

"Scully…" he began, before falling short to another coughing fit. "You have to know, before I die—"

"You're not dying," Scully said furiously, as fresh tears spilled from her cheeks. She slammed her palms against the door. "You're not. I'll find a way out of this. I'll find a cure for you. Just open the door."

"Even you can't get me out of this one." Mulder lifted his palm up so it was connected with Scully's again. "You need to know, Scully: I love you. I love you more than anything."

"God, Mulder—" another sob wracked Scully's body— "I love you too. I love you so much."

Despite everything, a grin stretched across Mulder's face. "That's all I needed to know."

"Don't give up," Scully said. "You can't give up. You have to keep fighting."

"There's no hope for me," Mulder said, "but there is for you. You have to keep going, Scully. We'll meet again, soon."

"No, Mulder, no," she wept, "don't give in. Don't go. I love you. I don't want you to go."

"Sorry, Scully…" he wheezed. It was getting difficult for him to talk. "I love you…"

And then slowly, he slumped against the glass, his hand going limp as it slipped away from Scully's.

As Fox Mulder drew his last breath, Dana Scully sank further into the floor and howled.

She was truly alone in the universe now.