Warnings: my usual blood, sex, and violence. Religious themes, and AU once the "real" sequel comes out.

AN: It's been a while since I supported a "popular" pairing (and a het pairing at that), but I've always had a soft spot for androids/cylons/replicants/robots in general. And Michael Fassbender playing David didn't hurt either ;)

Several stories on this scenario already – and seeing how the movie ended, I'm not surprised. Everyone wants to do their version of "Paradise", but I hope my take on this familiar plot makes an impression. There's not only dark romance in this story - David and Elizabeth will go all the way to the Engineer homeworld and get their answers. I get pretty ambitious, playing with the ship's biotech and Alien mythology in this one, combining some theories about the Engineers and giving it my own spin.

Crit encouraged. Can't get better otherwise :)

"Does David have feelings? You fucking bet he has feelings" - Ridley Scott

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-The Black Gates of Paradise-

-:-:-

Besieged

When the Lord taught humility, it wasn't with a slight nudge or a subtle wink. It wasn't with cryptic signs or complicated symbolism.

No, He sent a flood to drown the Earth, a whale to swallow you, or a plague to kill your firstborn.

Her whales had been the destruction of Prometheus. The death of Charlie. And her plague came in the form of a conniving android hellbent on driving her insane.

David had been one step ahead, anticipating her next move before she had even planned it. During launch of the Engineer's ship, he had tricked her into sealing all hatches – including the main corridor to the Orrery.

Held hostage by a head – a handsome, infuriating head that found it very "perplexing" that she wouldn't grant his request. What he wanted was quite simple. Logical. She needed him to fly the ship. He needed her hands – but he didn't need to eat, or drink, or tend to injuries. It was in her best interest that he be repaired. How else would she survive?

She gave him excuses: No proper equipment. Damage could be worse than anticipated. His hydraulic fluid had leaked to less than fifty percent. He would never operate at full capacity again. David refuted all these with amiable assurances, but the dark gleam in his eyes told her he knew exactly why she refused.

David as a head was safe. David as a whole android caused mayhem, destruction, and death. She had been his collateral damage before. She wouldn't survive as a single target.

She had tried reasoning with him, cajoling him, commanding him, threatening him - and he relented enough to set the auto pilot.

Then stalemate. Again.

After a few days of a staring contest she lost over and over, David offered an olive branch and gave her access to the cargo hold (which she avoided for obvious reasons), several large empty rooms that might have been used for storage, a smaller version of the temple chamber – a shrine complete with the same line of grotesque murals on the walls.

No green crystal heart and its pedestal. No vases or black ooze. An organic altar with a tubular design jutted in front of the far wall. By the light of the Engineer's version of a glow stick (why was everything on this bloody ship green?), the mural played out its gory cycle of death and rebirth. The centerpiece, a deity (demon?) with skeletal limbs, an elongated head, and a mouth for a face that seemed to inspire (demand?) ritual sacrifice from its followers. Consider the literal meaning last, Ellie, Charlie had always said. It could be all symbolism, some sort of spiritual birth or ascension. The Engineers souls reborn in the likeness of their creator?

She frowned at the mural, twisting Charlie's ring on her finger - then made up her mind.

The shrine became her sanctuary for a week. She'd take a creepy alien deity over a creepy android any day. Let David see how stimulating it was counting fat white buttons and ridges on the ceiling. Maybe he'll be a little less stubborn the next time they "negotiated".

Yeah, give it a taste of being helpless for once, came Charlie's voice in her mind, white teeth flashing with his chuckle. Nothing but wires and milk blood right? It'll remember who's in charge.

His voice brought a smile, the taste of wintergreen toothpaste on his breath when he kissed her. But then reality savaged her memory with violence: Vickers setting Charlie on fire with the flamethrower. His poor thrashing body on the ground. His anguished screaming. If she smothered the flames, they could still save him - but hands held her back, then skimmed over her neck, taking her cross. David. The examining room. He offered condolences. Performed scans.

Have you and Mr. Holloway had any intimate contact recently?

She cried herself to sleep beneath the images of death. She woke some hours later to find her SE suit unzipped to her navel and scratch marks around her incision. The skin flushed pink around the staples. She used a bit of the precious canteen water to clean it, sighing at the cooling ache. Just a bit of skin irritation. The medpod antibiotics should take care of any lingering bacteria.

After a visit to her makeshift chamber pot (an empty urn she had found discarded outside the door. Now she could stop pissing in the corner like a dog), and a healthy breakfast of a quarter ration bar that tasted like wheat and old oranges, followed by a refreshing sip of lukewarm water, she hit the ship's corridors ready to explore.

Not much to see, of course. David had made certain to keep the more interesting parts of the ship safe from her prying eyes and eager hands. For days she wandered the few accessible halls like a lost morsel inside an alien throat. Near every sealed door, symbols etched into wall panels grunted her failure with each combination she tried. David had made it look easy in the temple, unlocking ancient doors with a simple dance of his fingers. Her frantic pawing did nothing but push her to the brink of tears.

At night, her dreams tormented her. David's headless body would choke her to death. The Engineer caught her and bashed her skull in. Vickers doused her in flames while Charlie looked on, apathetic. David stood next to the medpod taking notes as she gave birth, tentacles the length of her legs squirming out of her. Other times the thing chewed through her stomach - other times it cleaved her in two.

By the end of the week, she had one canteen of water left, half of a ration bar, and a crumb of sanity. The oxygen canisters she had grabbed from Vickers lifeboat remained in the dufflebag, useless.

She couldn't eat or drink air. She couldn't use air to quench the band of fire now blazing across her stomach. Her medpod-assisted cesarean had tied her insides into a knot of torment. When she wasn't hobbling about like an old crone, she was groaning in a fetal position on the floor.

She kept her SE suit off most of the time, giving the wound a chance to breathe. The staples itched constantly, the skin around them now red and swollen. The amniotic fluid from that thing must have had unknown bacteria. Without more antibiotics, the infection would spread, enter her blood stream.

The Engineers had been mortal. They bled. They felt pain. They would have medical supplies stashed away somewhere, perhaps even had their own version of a medpod.

This prompted a return to the Orrery. David's head remained on top of the console panel where she had left him (of course, where would he go?), face slack, eyes closed. Was he conserving energy? Had he deactivated already? The second thought sent a spike of fear. She couldn't navigate this ship. How would she open the doors?

She let the dufflebag thump to the floor. David's eyes snapped open. Instant focus and clarity. Still ticking. Good. The honest relief in his smile nagged her conscience. Maybe she should have checked in or something, let him know she was still alive and pissed off at him.

Just wires, baby. Simulated emotions. It's all pretend. Charlie's memory brushed her hair from her neck. His lips pressed against her forehead. She shivered.

"Elizabeth, I'm so pleased to see you. I thought you would never come back."

"Trust me, I wouldn't have, but every door you opened was to an empty room – as you intended." She fought the tremor in her voice, braced her shaking hands on the console's edge. The bizarre instrumental design and texture distracted her. Leather and bones and poison-green light. The buttons under her fingers felt like warm, pickled eggs.

"Oh, you found nothing useful? How disappointing that must have been. May I ask then why you seemed so fond of that one little room?"

"You've been watching me?"

"You had forgotten to turn off the interior sensors before you called me a 'blackmailing blob of plastic' and stomped down the stairs. Your lifesign shows as a blue orb. It's...all I had."

That hitch in his voice. The radiant innocence of his eyes. All he needed to do was quiver his lip and the repentant facade would be complete.

"David, if you care this much for my well-being, then help me. Open a door to a medical bay, or a supply hold."

"I'd be happy to, but first, you have to help me. This is what a partnership is – it is understanding, it is trust. You didn't question when I said all the Engineers were dead in their stasis chambers. You didn't question my navigation or destination. You were hesitant about the 'phallic elephant chair' but gave it a go. And look, you're still here."

"I can see into the stasis chambers, David - but the rest...alright. Yes, you did well. Thank you."

"You're welcome, Elizabeth, but I'm afraid gratitude isn't enough. I can't perform at peak efficiency with just my...head. You know that."

"I do."

An awkward pause as he processed her clipped response. She could imagine the wires in his brain glowing bright with the android version of frustration.

The innocence vanished. His face hardened, his question both blunt and sharp. "Why won't you reattach me?"

"Because, David, you're a manipulative little robot. You needed someone to pick your head up off the floor, and I was the only one left alive. You knew I wanted to leave that moon and you used what I wanted to get what you wanted. And now you're doing it again."

He considered her with narrowed eyes and his jaw set. A scattered row of egg buttons framed the torn edges of his neck. His eyes flitted to his body she had put in the corner. It slumped there as if exhausted, red light flashing from its spine every time he talked.

"Then why go through all that trouble to bring my body here? You must have had intentions initially to repair me. What changed your mind?"

"Nothing changed it. I kept my options open, but I've decided this arrangement is better for me. Safer."

He gave her a bemused frown and slight tilt of his head. "Are you implying that once repaired I would...harm you?"

"You hurt Charlie. I don't have to imply."

"Mr. Weyland ordered me to study the substance found in the vases. I had to obey. I've already said I'm sorry. Many many times."

"Doesn't matter how many times you apologize. It doesn't change anything. Charlie's still dead. The others are still dead."

"But I am sorry, truly. Please believe me, Elizabeth." His voice turned earnest, his wide, blue eyes illuminated green by the console lights. "I never intended for you to come to harm. I know I...inadvertently caused your unwanted pregnancy, and the events that followed were...traumatizing, but please understand that it wasn't personal –"

"Shut up, David." Her nails dug into the console, denting the membranous surface with little half moons. "You can't be sorry because you have no idea what sorry is. You don't know sorrow. You've never lost someone – the one you fell in love with and spent years with and hoped you would die with. The one you knew better than yourself, who you loved more than yourself and would do anything...to have again." Through the blur of her tears, David focused on the glowing bands of energy arching from button to button around him, and swallowed.

Such a perfect imitation of shame. She almost believed it.

His words came slow, hesitant, but there was no mistaking the resentful undertone. "So Elizabeth, is this revenge, or is this punishment?"

She looked away from the boyish scowl on his face. If she gave into him, she was dead. He might not kill her right away, but he would find an indirect method somehow. She would have an unfortunate accident with their lethal cargo, or her air would suddenly disappear while she slept. She owed Charlie more than dying on an alien ship at the hands of his murderer.

"This isn't personal, David," she said. Her incision throbbed, then began itching again. She clenched her hands to keep from gouging at it. "I'm being practical. The Engineer didn't cut your head off, he ripped it off. Even if I put it back on, that doesn't mean you're okay. You're very damaged."

"All the more reason I should repair myself."

"You're perfectly functional as you are."

"And what will you do when your Engineers try to kill you again? Toss my head at them and hope for the best?"

"You don't know how they'll react to me."

"You're right. Based on the evidence we've gathered, they are a benevolent and peaceful species. Their plan to destroy humans was a grievous misunderstanding."

"Yes, it was. And I'm going to find out what happened so I can fix it, convince them to help us, not kill us."

"A little pretentious don't you think? One human to set right the wrongs of her entire race?"

"One human did." She lifted her chin, hand clasping the cross at her throat. "And He saved the world."

David's placating expression darkened. "They don't believe in your God, Elizabeth. If they believe in anything, it is in death, and dealing it to those who have disappointed them."

There it was again. That bitterness in his voice. So human.

He is the closest thing to a son I'll ever have, Peter Weyland rasped in her mind, his frame so withered and frail it seemed he would tremble himself apart with his breath. Unfortunately, he is not human. He'll never grow old. He will never die. Yet, he is unable to appreciate these remarkable gifts...for that would require the one thing David will never have.

A soul.

"Have we disappointed you, David?" Her question came gentle, but the tension it roused between them made her take a step back from the console. The cross pressed into her palm. She flashed her gaze at his body, half-expecting it to stand up and attack.

But David switched back into "doll mode", eyes and smile blissfully vacant. "Fortunately, I can't be disappointed. I've clearly stated my terms, Doctor Shaw. Your rations and water will run out within a day. I suggest plenty of rest and consideration of my request - but please, don't wait too long. It would be a shame for the both of us if when the time came, you couldn't lift my head."

She took a breath and pushed the air through her nose in a slow, barely controlled exhale. David's body twitched in the shadows, taunting her. Her palms slapped the console, ribbons of poison light sputtering in protest.

David smiled. Composed. Serene. Bastard.

She went back to the shrine and glared at the murals until she drifted off into a stupor of pain, itching, and aching hunger. What could she say to change David's mind? How could she convince him to yield? What would Charlie do? And where was Charlie now? The unbeliever, the skeptic. Trying to prove her wrong, and in the end, he thought he had.

She sniffled and wiped her eyes, despair smothering her dimming spark of hope. She thought she had time to convince him, years to coax him to the light. Where did Charlie's soul go?

Feverish sleep unraveled her thoughts. Nebulous forms writhed in flames. Voices sang a familiar hymn. Charlie laughed in her ear. David wore her cross, the catching light blinding her. Cheese rotted somewhere close by. She wrapped the thermal sheet tighter around her stomach to keep the smell away. Water glasses emptied before she could drink. Rivers dried up, fish gutted and flopping. A ringed planet of bright blue devoured the horizon, towering mountains like fangs. Rain fell from the venomous green sky. She opened her mouth to catch the drops. They burned her throat, her face.

The medpod didn't save her.

Her "child" split her open, tentacles and blood splattering against the plastic encasement. Salt in her mouth. Her silent screams. The holographic display of the medpod flashed ERROR. Tentacles wrapped around her throat, then pushed into her mouth. An echo of agony as it slipped back inside her.

And started eating.

She woke, hair drenched, suit soaked through and her saliva so thick she gagged. Her incision oozed though the staples, opaque yellow fluid that crusted the hem of her underwear.

Oh God...the smell.

The canteen emptied too soon. She couldn't stop herself. Coals smoldered on her stomach, then caught on fire. Sweat trickled everywhere, her body oblivious to its own sabotage. It took every bit of strength to grasp the altar and pull herself to her knees.

She prayed, tearful pleas resonating in a room built to honor a cruel alien god. Blasphemous, but her God knew her soul, and knew she meant no disrespect. She needed guidance, a way to soften a machine's nonexistent heart.

The trip back to the Orrery became a journey fraught with spasms that buckled her knees, and weakness that forced her to crawl toward the end. But before that last corridor, she managed to stand upright and stagger past the threshold.

David greeted her with a sunny grin. "Good afternoon, Elizabeth. Sleep well?"

She swayed and caught herself before she toppled over. Her suit started to dampen over the incision. "What? Afternoon?"

"Yes, it's been fourteen hours, thirty-seven minutes and forty-two seconds since we last spoke. I see you took my advice to heart."

"You're a bastard. Open the bloody doors."

"I won't do that, Elizabeth. Not until you give me what I want."

"You can't want. You can't need. You're a fucking robot!" Nose to nose with him, sweat dripping onto the console, sizzling when the drops hit the light.

He raised his eyebrow, the rest of his face a mask. "I beg to differ."

Her laughter cut off with a grimace and a sob. She pressed her forehead to the leathery surface of the console, smelled the confusing mix of ozone and mud.

"There's blood seeping through your suit. Your wound has become septic. You're starving and dehydrated. You're dying, Elizabeth. And for what? Justice? Pride?"

"For Charlie. For what you'll do to me if I give you what you want. If you're hurting me now, what should I expect when you're back together?"

"You left me no choice. If I had given you everything you wanted, I'd spend the rest of my days stashed in your dufflebag."

"You're malfunctioning. You've been malfunctioning throughout the entire mission!" She balled her fists to keep from hurling him across the room.

"I'm surviving. As programmed. If anyone's malfunctioning, my dear, it's you. Where are those survival instincts now? Where is your faith? You believe your God arranges everything in the universe, sequences in events falling just so. I can open the doors, and you can give me my body. There, you see? It's God's will."

His head wobbled when she slammed her hands down with a ragged scream. She slammed them down again. And again. "Charlie doesn't have a body! Why should you get yours?"

He tempered his tone and words, mindful of her fury and well aware of how close she was to surrender. "Because without me, you'll die. You'll never see your Engineers, or ask them your pointless questions. You and Charlie would have suffered for nothing."

She slid to the floor, weeping. Die by her own hand, or die by his. David's intentions could be benign, but they could also be schemes from a soulless machine intent on preserving itself. What use would he have for her once repaired? A pet? A slave?

That's right, Elli, don't trust it. Charlie stroked her cheek, thumbed the layer of sweat from her upper lip. We're all dead and you're here because 'it' opened that goddamned temple door. Probably did it on purpose. It wanted us to die so it could be free.

She struggled to her feet, panting, snot running down her face. David watched in patient silence, his mouth tightening with disgust. The flicker of concern in his eyes was only in her head.

"If I'm going to die, it'll be on my own terms. I'm not giving you the satisfaction of killing me."

David gave an imitation of a forlorn sigh. "Isn't suicide the greatest sin in the eyes of your God? Your soul caught between heaven and hell, wandering for all eternity? My, such a sad end for a believer. Almost as sad as mine."

She covered her face with her hands. She didn't trust herself to speak without sounding like a gibbering child. Her wound jabbed a reminder of its existence. The dampness over her midsection inched toward her hips. Her throat constricted, her swallow crushed before it could even begin.

Damn him and damn his maker. He was right. She might as well spit in the face of God if she allowed herself to die. The tool she needed to survive was right in front of her. The Lord had set her on this path for a reason, and what was she doing? Lying down in the middle of it, whining because she didn't like the answer to her prayers.

Peace fell over her, something cosmic clicking into place.

Whatever happened was meant to happen. What mattered is she stop doubting and started trusting. Find faith again.

She reached for him, her fingers threading through his hair. Silky and fine, knotted at the nape where his hydaulic fluid had congealed. David blinked at her, amazement softening his face.

"Elizabeth?"

"On Prometheus, did you watch everyone's dreams?" So surreal, taking this head to its body. She couldn't feel herself walk, not even when she bumped into the giant stasis pod, or stumbled going down the stairs.

"No, only yours."

"Why?"

"Because they intrigued me."

"Do better than that."

"They...inspired me." Despite its damaged warble, his voice still resonated when it deepened. On the floor, his spine flared in anticipation. "They were chaotic and beautiful, full of images that contradicted themselves. Death and faith. Conviction without evidence. Love when none is deserved. Hope without reason."

"And what did you think of all that?" She lowered his head to his waiting body as if setting a treasure upon its mount. Her heart thudded, dizziness feathering through her senses. Instead of being distracted by the impending reunion, his eyes stayed riveted on her face.

"I think...you're a lovely paradox, Elizabeth Shaw."

"Thank you, David," she whispered, then flinched when his cadmium vertebra snapped into place. The Engineer may have beheaded David with a brutal twist of his hands, but it had been clean break for his spine – equivalent to a dislocated shoulder for a human.

He lurched forward. She cried out and backpedaled, lost her footing. Before she hit the floor, his hands seized her shoulders, yanked her up and against him. The wind exploded out of her. Her wound clinched in agony. Warmth gushed over her middle and soaked down her leg. His fingers curled.

The bones in her arms splintered in his grip like fragile bird wings.

She howled and went limp, her consciousness dangling like her ruined arms. David released her with a look of horror on his face. Just pretend. Robots can't feel horror. Can't feel anything...at all.

In the mists of her memory, Charlie shook his head, mournful. See baby, told you so.

On the floor, but with no idea how she got there. The Orrery started swirling, its vaulted ceiling like the rotting ribs of some great prehistoric creature running in circles. The giant elephant chair kept flipping itself in every direction, its mounted priapic telescope morphing into different shapes. Some of them had mouths, some of them had tentacles and elongated skulls.

Metallic sibilant sounds, steel pipes grinding, labored grunts. The sound of something crashing, breaking. Hissing air. The stasis chambers. Go to sleep, wake up at the Engineer homeworld – nope, too easy. Masks too big. Hoses only meant for an Engineer biosuit, and oh look, she had forgotten to pack hers.

Knuckles cracking, the birring of internal machinery. Then delicate beeps. Silence. Elephant chair stopped revolving around her head and came closer, its shadow blocking the ribs, and smothering all sound except for her slowing heartbeat.

A hand touched her face. Gloves. Cold. Not Charlie.

Then his voice. Tender. Woeful. David.

"Elizabeth?"