"If a coin comes down heads, that means that the possibility of its coming down tails has collapsed. Until that moment the two possibilities were equal. But on another world, it does come down tails. And when that happens, the two worlds split apart."

― Philip Pullman, The Golden Compass

He's coming for you.

It took longer than perhaps it should have for the icy stab of realisation to ricochet through Shaw's shaking, adrenaline-addled body. From her hiding place amongst the clutter of Weyland's belongings strewn about the deck, she found her fingers idly stroking the handle of the axe she'd found as she quickly weighed her options; backed into a corner, the adrenaline demanded she fight. The searing pain in her lower abdomen disagreed, resisting the painkillers she'd administered moments earlier with a series of rapid spasms that threatened to choke an agonised cry from her throat.

She'd seen the monstrous creature that was now stalking her incapacitate her crewmates in less than a minute, whilst under fire. It had glanced off the rifle blast with nary a flinch and continued on its rampage, carving up the entire away team as if they were ragdolls. There was no way she could take it on with any expectation of winning; she felt a fool for even entertaining the idea, however brief it was. These last moments would be seared into her nightmares for years to come, once this was all over.

If she survived at all.

Another spasm ripped through her wounded body, the howl of pain that immediately followed lodging itself in her throat again. If the medicine didn't do its job soon, she would end up giving her hiding spot away. The slightest noise could…

David.

Sucking in a ragged breath, her finger hesitated over the comm panel. The android was clearly still functioning, and probably had little idea she'd chosen the coward's way out; if he interrupted her, it would all be over in a heartbeat. She could always reactivate the system later, once she'd figured out how to avoid being horrifically killed by either of the two monsters now baying for her blood.

Shaking, her finger finally depressed the button that muted the comm.

The die was cast. Coward it was.

The sound of strong hands prying at the airlock froze her blood once more. Bang, bang. Scrape.

Pressing her eyes closed, she willed her breathing to slow and hunched further, hoping against hope she would become so small, so compact, she disappeared completely from this godforsaken room. It didn't take long for the creature to gain access, door hydraulics whining under the strain of being pried apart and forced backward into their alcoves; she heard its armour catching against the door locks as it squeezed itself through the gap, its deep gasps for air echoing about the damaged walls amid deafening silence.

Slow, heavy footsteps paced about the room as the creature's breathing soon slowed. She didn't dare open her eyes as it appeared to pause, falling eerily silent for what felt an indeterminable stretch of time, the faintest of breaths the only marker of its presence behind her at all. It took another pace as she sucked in her lower lip, biting down on it hard as another spasm of pain threatened to force bile into her throat. Admittedly, this spasm was far less severe than the last few – a sure sign the painkillers were finally working.

Out of nowhere, the crystals hanging from the ceiling gently brushed against one another; gentle, musical, their tinkling could not have been caused by anything other than a deliberate touch. The Engineer was still here, still behind her, and apparently taking great glee in taunting her. Apparently in no rush, it fiddled a little longer with the chandelier before taking another few paces, pausing again, and softly exhaling. With a brief, gentle rustle, the sound of the pages of a book being leafed through resounded against the bulkhead she was crammed against – what on Earth was it doing?

Peeking one eye open and gingerly glancing upward, she could see only the gentle sway of a handful of the crystals above. How much time had passed? Minutes, hours? Each second of the creature's presence had felt like an eternity, hammering at her sanity, leaving her wondering just how much longer she could stay cramped in this position with each that groaned by.

With the softest of sighs the Engineer stood and scanned the room again. Both eyes now open, she could see the very top of its head over the apex of the bar's countertop, presumably facing away from her given his hands were not around her throat, and she was not airborne. Yet.

Thunk.

Swallowing despite herself, Shaw had no doubt in her mind what that was. She'd almost forgotten about the screeching, tentacled nightmare locked in the infirmary in her haste to hide from the other alien intent on smearing her across the carpet; her mind briefly ground to a halt as the scope of her predicament dawned on her, realising that unless the two were introduced, she would have to deal with both of them at some point.

Part of her briefly mused the value of sparing herself the agony and simply handing the axe to the Engineer. If her demise on this moon was inevitable, surely a humane exit would be preferable.

Slap. Screech.

The medbay doors shuddered beneath the trilobite's renewed assault, its screams raking at her eardrums and sending shockwaves of metallic horror through her teeth. A thick gasp permeated the air as the shaking trailed off, followed by near-silent, tentative footsteps away from her and toward the source of the unholy sounds.

Bang, screech.

Shaw was barely aware of the fact that she had been holding her breath. She snagged another as the medbay doors shuddered again, this time eliciting a distinctly humanoid shriek of horror from the other side of the room and a flurry of panicked squeak of footsteps against the polished floor; the sudden activity immediately preceded the deafening cacophony of groaning, twisting metal and a sudden increase in volume from the hellish screams from the formerly caged monster. The doors whined again, steel on fractured steel as the bent, twisted husks retracted as far as they would go into their housing in their current state, followed by a thick, heavy thud that shook the lifeboat against its precarious foundations.

So, her two friends had finally met.

Self-preservation finally fought to the surface, and she found herself peering past her hiding spot as the two creatures engaged in a clamour of equally horrific sounds in an attempt to ascertain whether she should leave them to it and run, or take a more proactive approach. Above the din she saw an inferno of long, sickly-coloured tentacles exploding from the twisted hole the creature had torn between the doors. The Engineer had seemingly tried to run, but not fast enough; fingers scrabbling desperately at the floor, it fought for traction as a tentacle dragged it by the ankle. She grasped for the axe handle as she watched, jaw agape, as the enormous humanoid slid across the deck back toward the screaming abyss of thrashing limbs.

Its frantic kicking with a free leg did nothing to halt its progress, nor did its violent thrashing and punching slow the grasp of more tentacles at anything they could reach. It let out another recognisably human howl as the slick appendages grabbed at both arms and legs, and eventually its neck, drawing it ever closer to the event horizon with its heart-stopping shrieks and screams.

She turned away, unable to take any glee in watching either creature suffer. Pressing her eyes closed again, she fought the after-images burned into her vision as the bedlam behind her continued. Somehow she was alive to witness this, and every fibre of her being wished she wasn't. Nothing, nothing, could have prepared her for an inch of this.

The Engineer's shouts had raised in pitch and become breathless in its panic as it thrashed against the cthulhesque monstrosity. She flinched despite herself as one of the shouts became more of a wet, strangled gurgle, her knee reflexively knocking against the countertop and dragging against a long napkin hanging from it; it slipped free, sending with it an almighty crash as the bottle of Vodka came to ground and breaking into several large, sharp pieces, followed by the distinct clatter of several knives bouncing across the floor.

Her finger trailed up to the top of her suit's zipper, lingering briefly where her cross should have hung. Her eyes couldn't stray from the knives that had fallen alongside the axe, fingers probing as her mind raced. In any other circumstance, in any other circumstance, she would not cower in the corner and watch the inevitable death of a creature. Given she'd all but discarded the opportunity of fleeing, citing a lack of viable places to flee to, and given she'd almost completely ruled out an intact escape, she allowed a tiny voice to finally probe her psyche as it kept pressing for attention; don't die a coward. Do something!

She couldn't decide whether it was the adrenaline still setting her limbs on fire, the painkillers finally dulling the burn, or the Vodka fanning the flames, but before she could stop herself she had forced herself to her feet. Bracing herself with the axe handle in one hand, she finally saw the full extent of the carnage over the bar; the monstrous trilobite had ripped a gap between the doors, but had bent them outward in the process and jammed them in place. The space wasn't quite enough for it to break free, but by God it was trying. It had a tentacle around each of the Engineer's limbs and one around its neck, and judging by the dents on the exterior of the doors, it had been slammed against them at least a couple of times. By this point the humanoid was bracing itself with both feet against the twisted metal several feet off the ground, left arm caught up in a mass of rope-like, slimy muscle while the right fumbled desperately with the loop around its neck. Its black, haunting eyes bulged and its pale tongue pointed and thrashed uselessly in its futile gasps for air. The noise, God, the noise…

An agonised gargle escaped the Engineer's throat, and the sheer humanity of the sound sent a pang down Shaw's spine. Her grip on the axe tightened as she slowly padded closer, jaw still slack as every sense remained fixed upon the battle before her. The Engineer's left arm seemed pinched, the fingers clenched in pain; before she could consider it too long, a mighty crack resounded through the lifeboat, as if a tree had split in half right beside her.

The scream that came from the Engineer despite being half-strangled told her all she needed to know. She knew exactly what had befallen it...and precisely what she needed to do.

Hefting the axe behind her and swinging it high above her head, she let out a scream of her own as she brought it down immediately above the pale, twisted hand. The door shuddered as the blade bounced off the alloy surface; from within, a high-pitched shriek all but deafened her as she swung again, ignoring the roaring pain in her abdomen, and forcing the blade through a second tentacle as the first fell away, a writhing mess upon the stained floor. The rope around the Engineer's throat fell to the deck with a sickening slap, followed by a series of panicked, ragged gasps from its victim.

With a violent spasm and renewed screeches, the creature slammed itself against the interior of the doors and sent more tentacles through the gap toward the Engineer's head. She swung a third time, primally aware of the stitches tugging at her ruined flesh but refusing to give the pain agency over her, embedding the axe blade in the tentacle that had again wrapped itself around the Engineer's neck. With the ringing in her head and her vision refusing to stay entirely focused, she wasn't quite sure whether it was a tentacle or a face she'd knocked the handle against as she wrenched her weapon free.

From the corner of her eye she noticed the creature within had begun to change, seemingly opening up and presenting the most repulsive of mouths – if it could be called that. Another scream from the Engineer, this one of complete terror, had her whip around to catch a glimpse of its face; it was desperately trying to scramble away, energised anew in its efforts, black eyes fixated in utter terror on the gaping more before them both.

She raised the axe again, idly wondering if she had the strength and accuracy left in her to deal a solid shot between the doors and into the behemoth's most frightening features. It left her little time for consideration, suddenly shooting forth a long, pale appendage that seemed on an intercept course with the Engineer's face.

One last time, she swung her axe.

A torrent of vile fluid spewed from the wound as the creature jerked backward, losing its grip on its victim as it fell from the doors and sprayed an arc of foul-smelling filth through the gap on the way down. The Engineer fell astride the doors, pulled to one side by the seething mass of flailing tentacles before being peppered with splatters of the greenish muck. After a moment, the fluid began to hiss where it fell on the floor and across the Engineer's biosuit; soon it began to do the same thing to the blade of her axe, bubbling and fizzing as whatever the substance was began to consume the metal. Compulsion won and she jerked away, thrusting the damaged weapon against the pile of limbs before her as her insides spasmed with the sudden movement.

The trilobite's howls had quickly dulled as its meaningless flailing lost strength; on the other side of the door, ragged gasps permeated the air as the Engineer continued to thrash against the slackening tentacles, legs and right arm desperately pushing the slimy masses away and writhing across the floor. Its left arm remained hitched in front of its broad chest throughout the ordeal, even as it staggered to its feet and quickly crashed back down again, knocking its left elbow against the deck and eliciting another agonised shout.

Pain returned with a vengeance as the heaving mass in the medbay shuddered to a gelatinous stupor. One hand reached down to tenderly grip her wound, instantly regretting doing so as several of the staples shifted in the process. She fell to her knees with a howl, both fists balled as she barely tolerated another series of spasms that felt like they would finally tear her apart. Distantly, she felt a string of snot and drool hanging from her lip as she gritted her teeth and sobbed through the searing pain; somehow she had not anticipated getting to this point alive, and now found herself without a plan for fixing the problem she'd just caused with that last burst of physicality.

Thankfully the medicine was still doing what it said on the label; with a few heavy gasps and a determined grunt, the agony had ebbed to something somewhat more tolerable and, as her vision refocused, she forced herself to kneel and check the status of either alien that could still, by all rights, cause her an agonising death yet.

Tentacles lay flaccid across the slick, stained floor, still and grey, as the creature behind the door continued to ooze. Across the hallway, huddled half-foetal against the wall, the Engineer cradled its injured left arm with the right, eyes squeezed shut as it apparently fought for control over its ragged breath. Shaw paused to wipe the mess on her face onto the shoulder of her suit before leveraging the wall beside her as she lurched to her feet.

Pale face contorted almost beyond recognition in pain, the Engineer's eyes shot open only when Shaw was almost on top of it. Its features appeared to yield to a myriad of emotions despite the creases of torment twisted across them, before pressing its eyes shut again and suppressing a strained grunt.

It occurred to her that she was now in a conundrum; without medical attention, she would surely die soon. Her presence was also now readily apparent to the far larger humanoid, who could still deliver her a death blow and spare her the ordeal of dying from her injuries. With the medbay ruined, the alien ship crashed, the Prometheus annihilated and without another soul alive to treat her, she found herself with few options, little to lose, and no frame of reference for an ounce of this madness.

Despite her better judgement, she made her way back to the bar. It had occurred to her as she reflected upon her last few minutes that she could at least go out having done some good; shuffling toward the mess strewn across its surface, she briefly picked through the clutter before grabbing a small, sharp knife, its long, pointed sharpening steel, and what she assumed to be a tablecloth. She stole a glance in the Engineer's direction – it hadn't moved, still grimacing and gripping its left arm. Good.

Wrapping the items in the tablecloth, she forced her way back over to the prone monster before throwing her wares at its feet and sinking to her knees beside it all. The Engineer's eyes flew open, locking an accusatory glare upon her own that left her momentarily transfixed, lost in the abyssal black that was its gaze; refusing to yield to it, she simply raised a bloodstained hand and pointed toward the huge arm cradled against the alien's chest.

It stiffened, sucking in a breath; she held her hands in front of her, cupping them in front of her chest and bent an invisible object back and forth as if testing its tensile strength. Something akin to confusion washed over what was left of its pale visage beyond the blackened burn engulfing nearly half its face, glancing between Shaw's hands and her eyes.

Pausing for a moment, she reconsidered. After further thought she raised her right arm, holding the forearm parallel to the floor, then tapped the centre of it with the index finger of her left before repeating her mimed gesture from earlier.

Understanding gradually replaced the Engineer's confusion. It simply offered a single, solemn nod, before letting its gaze drop to the floor with a heavy, ragged sigh.

Just as she thought; the screeching menace had broken one of the bones in its victim's arm.

Slowly, cautiously, she reached down toward the sheet she'd acquired. Whether her languid pace was to show she was no threat, or to avoid injuring herself any further, was moot. The Engineer watched with obvious trepidation as she dragged the sheet toward her, revealed the small knife, and immediately embedded in the fabric. The enormous humanoid looked as though it was about to take a swipe at her with its good arm just as she began tearing a long strip from the cloth, but hesitated as she refused to react to the threat and simply continued ripping. A second strip, and a third, and she cast the remainder aside.

She motioned with one hand in a come, hither gesture, raising one of the strips of fabric with the other; the Engineer doubled down, responding with a deepening scowl and nothing more. With a sigh she raised her left arm again, loosely and demonstratively wrapping the torn cloth around her forearm before shaking it off and making a gentle grabbing motion in the direction of the alien's left hand.

It seemed to scrutinise her hand for an unsettling period of time, only gingerly half-offering it with the support of the other hand, but not close enough for Shaw to reach without leaning far closer – which, of course, in her current state, she was unwilling to do.

What she did notice, however, was how swollen the limb was. It was significantly thicker than the right forearm, stretching whatever material the biosuit was made out of and most likely contributing to the pain significantly. The left cuff of the biosuit had pulled free of the creature's skin under the strain.

She cautiously mimed the size of the limb with a gentle grabby-hands motion alongside the hand; the Engineer nodded again, lips pursed thin. She gestured again, cradling the fingers of both hands in a 'hook' shape, and dragged them toward her; when met with another confused and accusatory glare, she repeated the motion before pinching at her own forearm, tugging the fabric of her suit toward her wrist.

This time, it understood; it extended one icy index finger, pointing at the knife just beyond its reach. After a moment's hesitation she reached down and offered it, the darker part of her mind wondering if this was where she would die from being stabbed with something usually used to cut limes. Instead, the Engineer slipped the tip of the blade into the cuff of the suit and tugged upward, starting a small incision in the thick material. Visibly wincing, it grasped the handle with a closed fist and pulled harder, angling the blade so it slipped between flesh and suit. The little knife struggled with the dense material, stopping several times and requiring more force as it encountered nodes within the sleeve. Swollen, purple flesh protruded from the incision. It was a mess.

It must have been a relief, because the Engineer's twisted expression had become one more of concern as it examined the injury. Casting the knife aside, it watched with distant intrigue as Shaw picked up the sharpening steel, briefly trying to twist the plastic handle free before resorting to grasping the tip and swinging the handle into the floor.

The Engineer flinched as the brittle black plastic shattered into several pieces, then watched pensively as Shaw removed what remained to expose a long, slim, blunt rod of hollow metal. She cautiously shuffled closer, holding the steel alongside the broken arm but at several centimetres' distance. The creature made no effort to stop her, perhaps realising she was trying to help – or, at least, that's what she hoped.

Unable to hold her arms at extension for very long with her innards torn to shreds, she shuffled closer again so that she could do what she had to do without causing herself any further injury. The enormity of the Engineer was all the more apparent when she was damn near pressed up against it, its knees level with her chest as she knelt beside the swollen limb. Finally she pressed the steel against the battered forearm as gently as she could, silently thanking her lucky stars as the creature made itself useful and tentatively grasped the end closest to its elbow.

Slowly, gently, she began to wind a strip of fabric around the thick, bruised wrist in front of her. The Engineer's breath hitched in its throat as it watched her work, still offering no resistance. She did her damnedest to avoid touching it as much as possible, instead leveraging the steel to get the bandage tight enough to work; it took every ounce of her focus to remain trained on the task at hand, not simply because of the ebb and flow of painful spasms through her core, but because at this point she'd noticed how the creature smelled. Above the foetid stench of the dead monstrosity in the medbay opposite them, and the vile-smelling fluids it had spewed against almost every surface, there was a heady air of masculinity that she found impossible to put her finger on, and equally as impossible to ignore. Whilst not particularly strong, it was pronounced enough that it permeated every other smell in the lifeboat, no matter how overpowering. She reasoned that it was probably quite unfair; all things considered, the creature was most likely male – if that meant anything in whatever world the Engineer came from.

She was certain for one horrifying moment that she was about to get punched in the head as it came time to wind the bandage around the actual fracture. The Engineer had let out a monstrous scream, damn-near deafening her as he immediately raised a clenched fist; teeth gritted, he eventually opted to instead press the fist against his mouth, eyes squeezed shut and breath held as he offered the limb back to her. Heart pounding, hands shaking, Shaw simply continued what she was doing.

It had never taken so long to splint a broken arm, she mused dryly as she tied off the last of the bandage around his elbow. There were a multitude of reasons, not least of which was the sheer size of the limb. The Engineer reluctantly raised his bandaged arm once Shaw leaned back, wincing again as he manoeuvred it back over his chest, briefly cradling it with his right before offering Shaw an inscrutable gaze. Battered, exhausted, this was a very different creature to the one that had pulverised her crewmates not long ago.

The other creature had gone long enough without observation; a violent shudder and grotesque slop had both humanoids snapping their attention to the medbay in time to see the betentacled horror give one final spasm as something bulbous slid down through the severed tentacle-like protrusion hanging from its ghastly mouth.

What emerged from the monster was arguably even more horrifying; a blotched, goop-smeared sac of God-knows-what slid onto the floor twitching and pulsing as something inside thrashed about. Shaw heard the near-silent shuffle of the Engineer forcing himself to his feet. She shifted aside as he slunk past her, stepping gingerly between the flaccid tentacles across the floor as he reached down for what remained of the axe with his right hand, then unceremoniously brought it down upon the writhing mess between the doors; with a wet squelch, the thing's movement was no more.

The Engineer turned back toward Elizabeth after a moment, cradling his left arm close to his chest as he stepped back through the mess of tentacles; the confusion and disgust written across his face mirrored her own abject horror. It occurred to her that now was probably her time, the injury strapped and the beast slain, but before she could consider the ways in which he might kill her, his deep, split-tone voice permeated the silence.

Whatever he'd said was of course utterly lost on her, though his intent gesticulating with a pointed finger toward the heap in the medbay cleared at least some of it up. As her gaze flitted between the two enormous aliens, he repeated some of what he'd previously said slowly, deliberately, while making a broader, more sweeping motion with an extended arm.

Another spasm of pain ripped through her gut as she shifted; the hand that she pressed against the wound and then retracted came back blood-stained, sticky and fresh. At a glance, it seemed her suit was now soaked along the incision. Alright then, two birds with one stone.

Drawing a breath, she pinched the suit zipper and yanked it down; gritting her teeth to dull the howl of agony that would surely have otherwise ruptured eardrums, she squeezed her eyes shut and drew ragged breaths and willed the pain to subside enough that she no longer felt the need to hurl her guts onto the floor.

For the briefest of moments, a tinge of awkwardness fell across the Engineer's face; it didn't remain long, as the raw wound quickly caught his attention. Through her hazy, swaying vision, she saw the mighty creature turn away and momentarily bend over, just as her ringing ears caught the faint lurch of a dry-retch from across the hall. Blinking away the coloured blobs that had threatened to overtake her vision, she raised one feeble, quaking hand and pointed toward the splattered mess behind the bent doors, the other squeamishly tugging apart her suit to reveal more of the wound.

The expression she met was one of contorted, mortified disbelief as the Engineer's eyes bulged, jaw going slack, morbid realisation knocking the wind from his chest. For a moment, he appeared as faint as she felt. But the cold air against her reopened wound had awakened a sense of urgency in her that hadn't been present until she'd torn her suit open; she needed to reassemble herself, and with the surgery pod in a state of ruin, she knew she was staring down the barrel of doing it manually.

And there was a grey, stinking hulk stopping her from doing just that.

Once the Engineer's horrified gaze returned to her, she quickly mimed a stitching motion from one side of the wound to the other, face pinched as she raised a finger and pointed toward the medbay.

Fair's fair, big guy. I helped you, now you help me.

Author's Note: I finally got around to watching Prometheus in its entirety. Generally speaking I can't do gore, and I manage to chicken out at the slightest hint of it; this time, I forced myself to watch the whole damn thing. At one point I even managed to almost puke. Amazing.

It's all for this, though; the other latest story of mine is actually the sequel to this. Or, put another way, we should probably figure out just how the damn Engineer ended up on a prison base in a different galaxy instead birthing a horrifying stabby nightmare.

I'm writing this from Shaw's point of view, but I'll also be writing in parallel from the Engineer's point of view elsewhere; though this is an unapologetic 'fix-it', I intend to do one of the many things that Prometheus never did - character development. And boy do I have plenty.

In short, this is one of those 'what-if' stories where the Engineer survives, and explores just how that manages to happen. I know some people will RIP THEIR UNDIES over this (as I'm discovering, somehow, the Alien fandom is even more terrifying than the Star Trek one), but you know what they say about fanfiction...if you don't like it, hit the back button.

I think we're mostly done with the gore for now. Goddamnit I hate gore. Good lord. Fair warning though, I am leveraging a lot of original material that was cut - both one of Scott's original intentions, and a fair chunk of the cut footage from the latter half of the movie.