Title: You Light The Skies Up Above Me
Characters/Pairings: Sherlock Holmes, John Watson, Jim Moriarty, Greg Lestrade, Mrs Hudson, Mycroft Holmes. Johnlock, hints of Mystrade.
Genre: Alternate Universe (Stardust), Romance
Ratings/Warnings: PG-13 (to be safe for the last bit)
Summary: The first thing John Watson is aware of is that his right leg hurts like hell. Crossover AU with Stardust. The song quoted at the beginning is from "Rule the World" by Take That.
Disclaimer: I do not own the BBC adaptation of Sherlock or Neil Gaiman's Stardust.
Notes: Written for donttalkoutloud for the Johnlock Challenge Gift Exchange. Uses primarily movieverse canon, with some bookverse details (like Yvaine remaining after Tristran's death).
A huge thank you to my friend Sierra, intelligentairhead, and especially greyofthiscity for beta reading!

you light the skies up above me
a star so bright you blind me
don't close your eyes
don't fade away

primus.

The first thing John Watson is aware of is that his right leg hurts like hell.

The second thing is that his left shoulder also hurts like hell.

The third is that there's a jewel lying next to him.

He shakily raises himself into a sitting position, dusting off his silvery robes. His light-coloured hair shines silvery in the moonlight as he casts his eyes heavenward to his brethren. He can almost hear Astra laughing at him, so he shakes a fist in retaliation as he picks up the gemstone with his other hand.

It is, on closer inspection, a bright blue carbuncle – odd, really, considering most carbuncles are red. John slips it into the folds of his robe; his hand barely leaves his pocket before a bright glow lights up the night sky once more. Out of the sky comes another ball of light, and moments later a bright something barrels into him.

John is thrown back onto the ground with an 'oof!' of surprise, and when the glow clears he sees that a young man is lying on him, looking down at him with a frown.

"You're the star," says the man.

"Way to be blunt," John retorts.

"But you are the star."

"We've established that."

The intruder pauses, notices their positioning, and clambers off John with a grimace.

"Sorry," he grunts, straightening up and dusting off his cloak and clothes. From the ground, John looks up at this intruder, who's tall and imposing and not just a little frightening. His face is pale in contrast with his unruly dark curls; his eyes are a silvery pale like the moon; his cheekbones are high and aristocratic.

John's not sure why his breath feels short.

"You were knocked out of the sky by a blue carbuncle, and you've broken your leg," says the man, kneeling down again. "I suppose I could help with the latter."

"That's comforting. You supposing anything, that is." John grimaces at the shard of pain that jolts up his spine when he tries to move his right leg. The man points his finger towards the leg; moments later John can feel the pain ebb, but cold panic seizes his heart in the same instant and he scrambles away.

"You're a witch."

"Warlock. Do I look feminine to you? Do your research."

John draws a silvery dagger from his robes as he clambers to his feet. "Whatever floats your comet. Just stay away from me."

"I don't want your heart, star."

"My name is John," John snaps, not sure why he's disputing his name with a warlock, of all people. They're circling each other now; John's eyes are narrowed and his legs are bent slightly, ready to bolt at the first sign of aggression from the warlock.

"And mine is Sherlock." Sherlock sounds almost amused by it all. "I'm actually looking for that blue carbuncle that knocked you out of the sky."

"I don't believe you."

"Of course you don't. Not with the witches once conspiring to kill and eat the hearts of every star that bothered to fall within a thirty-thousand mile radius of Stormhold. But I believe three of them died attempting to do that to the current queen. So really, I pose no threat to you."

John lowers his knife, but his brows are still furrowed and his shoulders still tense. "I suppose I have no choice but to –"

He is broken off by the sound of screaming crows.

II

The converging murder of crows bears down on them, beaks flashing like knives, eyes glinting evilly in the moonlight. Abruptly, the warlock darts forward, grabbing John by the wrist.

"Hey!" shouts the star, but Sherlock is pulling him away from the oncoming flock, towards the sides of the crater. "I can walk on my own, thanks!"

"Don't stand there like a damsel in distress! Run!" Sherlock hollers back at him, and John raises an eyebrow, wrenching his wrist from Sherlock's grasp.

"It'd be better for you to avert your eyes," John says as he turns about, and suddenly he is glowing, bright and blinding, shielding the two of them from the crows. For a moment he shines brighter than the sun and the crows fall back, blinded, routed, completely lost –

As the light begins to fade from John's being, he turns to see Sherlock gaping at him. He raises an eyebrow. "Who's the damsel in distress now?" he asks, smirking as he starts mounting the slope out of the crater. He can hear the warlock following him. Once he clears the crater, John turns and glares at Sherlock, still scrabbling to pull himself out of the crater.

"Why are you following me?" he demands.

Sherlock raises an eyebrow; his laugh is short, sardonic. "You're in danger, John. Queen Yvaine of Stormhold wants me to ensure your safety."

"Funny how she'd send a warlock."

"Times have changed since those days," replies the warlock as he finally clambers out of the crater, shrugging. "Anything forcibly taken is only temporary. Besides, it is now a crime to kill a star."

"Yet I'm still in danger somehow?" John crosses his arms, narrowing his eyes.

"Yes," says the warlock, turning abruptly and stalking off, black cloak billowing behind him. John groans, but follows anyway.

"I can take care of myself, you know," he growls at the back of Sherlock's head. "Who's the one who just drove off a murder of crows? I could stay here. Or not follow you, that works too."

Sherlock turns at that. "I'm not forcing you to go anywhere," he snaps, walking back to the star and leaning in until their faces are only inches apart, until John can feel the warlock's breath and smell his vaguely chemical-like scent.

The star crosses his arms, looking up into those pale, moon-like eyes. "Stop following me."

"I'm in front of you. Why are you following me?"

John stares, before uncrossing his arms with a sigh. "I need a way out of that blasted forest ahead. Afterwards, it's none of your business where I choose to go." His eyes narrow. "I can take care of myself."

Sherlock snorts, as if he's doubtful of that. "Even if it's a crime to kill a star, not all witches want to follow the law," he replies, before pulling back and walking away once more.

secundus.

"Those crows were sent for you," Sherlock says as they start heading across the plain. The woods loom ahead. These particular woods are not serwoods, as far as the travellers are concerned, but they tread warily all the same. "I have reason to believe that you're part of some witch's demented plan for youth and power. The wheel turns, and the same spokes come up. Nothing's ever new."

John makes an amused sound in the back of his throat. Sherlock walks on before the star, his cloak wrapped tightly about him. Around them, the night sky is beginning to lighten, and John yawns several times before collapsing against a tree.

Sherlock stops, looks at him, and rubs his temples with a groan.

"What?" demands the star. "I'm tired."

"The person who sent the crows may still be after you. We're not safe over here at the edge of the forest."

"Yes, and I am tired," snaps John. "Tell me more about this conspiracy plot to kill me, Sherlock. Maybe that'll keep me awake."

"Keep walking, then," Sherlock retorts, and John grumpily ascends to his feet once more.

II

They enter the forest proper. The path is well-delineated through the trees; it is, after all, one of the more popular passageways in and out of this particular part of Stormhold. There are smaller detours through the trees as well, and the forest itself expands to the foot of the nearby mountains.

"So?" John asks after a minute or two of aimless trudging across the beaten forest path. "Who's out for my heart, if it's not you?"

Sherlock shrugs. "This morning we found a man dead at the border with Wall," he begins. "The man had a page torn out of a book called On the Dynamics of an Asteroid. Upon searching for the book we found that it was at the Royal Observatory of Stormhold and that the professor who resided there was dead. Murdered just like the man from earlier. Based on the acquired data, the murderer is a witch searching for something about stars."

"How could you have known?"

"Obvious signs of the strangulation spell – the bruising was uniform along the neck; there was no sign of a handprint." Sherlock pulls out a scrap of paper, handing it to John. "This page is about the properties of a star's heart."

John glances at the paper and tries to suppress the chill seizing at his heart. "I see."

"The murderer, after killing the professor, managed to escape out the window. However, the observatory is in a tall tower; the murderer must've used magic to prevent falling to his or her death. Moments later, the queen's blue carbuncle was stolen. Lining up the events of the murder – which must have been perpetrated by a witch – and the theft of the carbuncle, it becomes quite obvious that the witch who perpetrated these crimes wants a star knocked out of the sky. Queen Yvaine told me to ensure the star's safety and to bring back the carbuncle, so I lit a candle –" Sherlock pulls out the stub of a Babylon candle – "and thought of you."

"Well, I do have the carbuncle," John says thoughtfully. "You're saying that the idiot who tossed it up to knock me out of the sky isn't keen on just having me over for tea?"

"That's my hypothesis, yes."

"Fascinating." John pauses. "That's actually rather brilliant."

Sherlock turns to look at him. "Really."

John smiles encouragingly. "Yes. What can you tell about me, Sherlock, without resorting to magic?"

Sherlock taps his chin with a finger and frowns, looking John up and down. "You're a star, formerly hovering around the constellation of Ophiuchus, so you must be a healer of some sort. You were hit in the shoulder with the carbuncle, which is unfortunate since you've had a bad shoulder for a while, probably as a result of some sort of fight, more likely because you hurt yourself trying to mediate said fight. You were witness to Ingrid's fall as well as Queen Yvaine's, so you naturally distrust witches." He pauses. "Your closest sister overindulges on ambrosia."

John stares at him, momentarily winded. Sherlock smirks. After a moment, John coughs, and chuckles.

"That was utterly brilliant."

"You think so?"

"Yes. It was extraordinary. You swear you didn't use magic at all?"

"As if I would."

"Then my awe stands as-is. I take it you don't get many compliments of that sort."

"No, that's not what people normally say."

"What do they say, then?"

"Piss off."

John chuckles at the hesitant smile spreading over Sherlock's face. The forest, which has retained the dark for a little longer, begins to lighten between the trees, and John yawns widely before sitting down between some roots.

"Must we?" Sherlock asks, frowning.

"You try impacting the earth from outer space and then having to protect some blithering magical idiot from a bunch of crows. It's tiring." John leans against the tree. "Let me rest."

Sherlock huffs. "If you insist," he says. "I suppose I can find you some food."

"That'll be wonderful," replies the star, and closes his eyes.

tertius.

John wakes to a darkened forest with no warlock in sight.

His first thought is that he really shouldn't sleep through the day while on earth. Humans are diurnal creatures, after all, and if he was to avoid detection as a star he was going to have to live by the human sleep cycle.

His second thought is that even if it is night, Sherlock should've returned by now.

Clambering to his feet, John tries to assuage the anxiety and fear he feels as he looks around him at the dusky shadows between the trees.

"Blast it. Where's that warlock?" he grumbles. Sherlock said he'd get food, but there's no Sherlock and no food, and much to John's chagrin his stomach is growling.

He tears through the trees in search of tracks, fingertips glowing as he looks for Sherlock's footprints in the ground below. The prints head left, towards the west. John sighs and follows them as far as he can – but soon the prints become confused, muddled by others. The star tries to distinguish Sherlock's from the rest, but to no avail.

He starts wandering off in a random direction, hoping to find Sherlock somewhere in this giant, dark forest. The trees tower over his head, ominous and silent, whispering tales to each other in the tongues of wind and bird-whistles, and John shivers from the thinness of his silvery robes.

Light. There is light in the distance; John can smell smoke, the pleasant sort of smoke from a roaring fire in the hearth. The lights are on in a charming old cottage not too far ahead, and he is tired and hungry indeed.

He steps up to the door of the cottage and knocks.

A young man opens the door, black eyes lighting up as he sees John standing on the doorstep, shivering.

"Is there room and food here?" asks the star, rubbing and blowing into his hands for warmth. The young man laughs, but his cheer doesn't seem to reach his eyes.

"Certainly, certainly, come on in!" he says, beaming as he shuts the door. "Let me draw you a bath and get you some food."

John doesn't see the sharp, evil-looking knife tucked into the man's belt until it is too late.

quartus.

Sherlock rushes into the cottage with a clatter of hooves. Preceding him is a unicorn, bright and pure, but Sherlock is anything but, his eyes flashing in the firelight and his black cloak billowing beyond his shoulders like black plumage on a raven.

"John!" shouts Sherlock, and John, who had been lying supine on the bed in the cottage, sits up in alarm, the glow of relaxation fading from his body. The other young man drops something with a clatter; John looks down and sees a knife – a shining, star-killing knife – lying on the ground, and fear seizes his heart in a vice-like grip.

The other young man – another warlock –raises a finger to Sherlock with malice in his eyes, curses on his tongue. John reaches for his knife, but the man glares at him, and without warning the hilt of John's dagger turns red-hot and he yanks his hand away, hissing.

"You were the thief," Sherlock says, eyes trained on the other warlock as he stepped towards John. "This was all your doing."

"Obviously," snaps the man; he and Sherlock eye each other like prowling wolves. "The star's mine, Holmes; you will not possess his heart for a single second!"

"I don't intend to, Moriarty," sneers Sherlock, reaching for John nonetheless, moving to pull the star away from Moriarty's cruel gaze.

The other man laughs, and sets the cottage aflame in green. Sherlock turns to John as Moriarty, with knife held aloft, advances towards them. The unicorn is caught and consumed by the flames; it whinnies despairingly, as if urging them to leave.

"Here," Sherlock whispers to John, pressing the stump of the Babylon candle into the star's hands. "Light it, and think of theDeduction!"

"The Deduction?"

"Flying pirate ship, rebuilt from the Caspartine. We'll be safe there – trust me."

With trembling hands John grasps the black Babylon candle; Sherlock grips his wrist. John's not sure why his heart speeds up at Sherlock's touch – the warlock's fingers are cold, after all – but he squeezes his eyes shut and thinks of a flying vessel, fairly certain that he's glowing as he does so. Sherlock is close, too close, and his breath sounds erratically in John's ear as together, they plunge the candle into the green fire.

They're rushing through the darkness moments later to the sound of a knife embedding itself into a distant wall.

quintus.

There is a man whose umbrella taps against the captain's desk on the Deduction, which seems to be almost an exact replica of the sky-ship that had been the vessel of the infamous Captain Shakespeare. Sherlock, still gripping John's wrist, sweeps right up to the desk and levels a nasty glare at the man.

"I see you've been putting on weight again," he says by means of greeting. John frowns.

"And I see you've brought the star," replies the man. John tenses at that, hand straying to the folds of his robes, to the dagger still concealed in its sheath. "Where is it?"

"Where is what?" John asks testily, his hand closing over the hilt of his knife.

"The Queen's blue carbuncle."

John's mouth opens. "Oh. That. Why do you need it?"

Sherlock chooses that moment to interrupt. "And how is Lestrade doing, brother dear?" he asks as he looks at John, gesturing for the star to relinquish the jewel. John hands the blue carbuncle over to the man, who tucks it into his own grey robes with a smirk.

"Your… brother?" the star asks, brows furrowing. "How –"

"You could ask him yourself," interrupts Sherlock's brother, directing the comment at Sherlock. "And really, you ought to call him Greg; he's practically family."

"I'll believe it once you marry him, Mycroft," Sherlock replies, and John blinks owlishly at the two brothers until the aforementioned Captain Greg Lestrade strides into the room, looking gruffer than a billy goat and hardly the paragon of effeminate masculinity that John had suspected.

"I see you're still here," he says to Mycroft, but there's a gentleness in his eyes that belies the strictness of his voice.

"I've come to pick up something Sherlock promised me he'd seek on behalf of our Queen," replies the elder Holmes brother, smiling. "I shall be lighting a candle soon."

"Stay a little longer; there's no need for a rush," Captain Lestrade scoffs. "Besides, Mrs Hudson dotes on you two so very much." He pauses, looks at John. "Is this the star that came with the carbuncle?"

"The very same," Mycroft replies, and John cringes, tries to pretend he's no one special, just another part of the oak panelling in the captain's quarters. But Captain Lestrade laughs, informs John that he's clad still in his silvery star robes, and that he really ought to change into human clothing if he's going to go about undetected.

II

Sherlock smiles at him as well later that night, after John's found more suitable clothing. "You look… fine," he says, as the sky-ship sails through oceans of clouds, and John looks up at the stars, wondering if he can make out what his sisters are doing tonight.

"They're so clear from here," the star says after a moment. "Yet they're still so far away."

"Do you miss them?" Sherlock's voice seems unusually tender. John shrugs.

"Of course I do," he replies. "Yet it's not that bad down there, either. Excluding the whole 'conspiracy to kill me' thing, that is. Get rid of that, and I'd have a smashing time."

Sherlock chuckles, and John follows, and soon they're both laughing like there's nothing else to worry about in the world – for a moment it's just them and the stars, and everything to John seems to shine much brighter.

"I should thank you," he says, when their giggles finally subside, "for saving my life."

"You saved mine first," Sherlock replies, smiling at him still. "We're even."

John can't help but wonder if the warlock might actually like him.

sixtus.

"There's no need to pretend, my dear," Mrs Hudson is telling Sherlock. She's the cook on the Deduction, although Captain Lestrade likes to call her his other first mate (the actual first mate is a woman named Donovan, a very capable lass even though she and Sherlock are often at odds with each other). John is watching them, trying his hardest not to listen in.

They're moored in a small bay, the waves tickling the pebbles and heather of the shore, the gangplank rooted in yellowing grass. John steps off the sky-ship with more than just a little twinge of regret; Mycroft left by Babylon candle days ago, and Lestrade had been rather lonely with his going. John had endeavoured to cheer up the gruff captain by enlisting his help to learn the piano and the waltz.

Sherlock turns to see John, and a strange look crosses his face – a mixture between pleasure and fear, and despite himself John is glowing; he tends to do that a lot around Sherlock, doesn't he?

"Caring is not an advantage," Sherlock snaps at Mrs Hudson, who laughs.

"Says your brother, and look where that got him." Her eyes twinkle at him. Sherlock's eyes flicker to John, but John turns away, silent.

"What did Mrs Hudson say to you?" John asks later, much later, as they ensconce themselves into the bushy wilderness of Stormhold.

"If you really want to know," the warlock replies, scuffing at the undergrowth, "she told me that it wouldn't hurt to love what was right before my eyes, because you glow every time I come near you."

John looks up, barely able to breathe. He's fairly certain he's glowing brighter than a bonfire.

Sherlock looks away at the distant rumbling of carriage wheels. "I have always put reason before sentiment. I don't see any reason why I should cease now, star or not."

John's glow dies even faster than it comes.

II

Sherlock wants to take John to the Citadel of Stormhold, but John gives up on that plan later that night as he, wide awake once more, steals away in the night as Sherlock sleeps.

The world stretches out before him, but the stars seem to twinkle even brighter – beckoning him home, begging him to return to the sky where he'll be comforted, where he'll always have a place. If Sherlock wants to reject him, so be it. John is going to have to find some way to get home.

Despite his new resolve, John still can't help but toss a backwards glance at the copse of trees where Sherlock sleeps.

The black carriage, driven by a now ancient-looking Moriarty, bears down on him moments later.

septimus.

The blackness of despair has numbed him to the dreadful prospect of his own death. Even strapped down as he is to a cold, hard slab with a wizened, deranged warlock sharpening a knife he is about to thrust into the star's chest, John relishes in the fact that this time, he feels no fear.

There's not much more left in the world for a star with a broken heart.

"I should've preferred to get you in that fleeting moment when you were glowing brighter than the sun," sneers Moriarty, his reptilian gaze shifting to the placid mask of John Watson's face. "Damn that meddling Holmes; he said he didn't intend to capture your heart, and yet he refused it when it was so willingly given! See how he'll like it now when I've burnt it out of you, my pet!"

"Where is Sherlock?" John ventures, averting his gaze from Moriarty's ghastly visage.

"Dead. He woke up, found you gone, and took a little leap off a cliff."

It's as if those words are knives all on their own, small and cruel, embedding themselves into John's chest. He grits his teeth, trying to prevent any sign of his pain show on his face. Moriarty leers at him; the sound of a sharpening knife fills the air.

There is the screeching of metal, the grinding of bolts and gears. "Really," a familiar baritone resounds, and suddenly it's like there is a string attached to John's heart that ties him to the speaker, a string of crimson that, if pulled at or sundered, would somehow rent his chest in two. John turns his head towards the door, and a smile breaks over his face.

Sherlock Holmes, a bit sodden and worse for wear, stands at the entrance to the mansion with that same rage burning in his eyes. Moriarty laughs cruelly.

"Oops, must've miscalculated!" he says gleefully. "Well, in any case, you were a little too late. Sorry, dear!" And with that, he raises the knife to drive it into John's chest.

Sherlock raises a finger. The knife shatters. John begins to wriggle free from his bonds as Moriarty and Sherlock grapple with each other – first with magic, then with weapons, finally with hands (claws) and teeth (fangs) like ferocious wolves, and as Sherlock passes by he snaps his fingers at John's bindings, and the leather clasps spring free; John scrambles out of the way, rushing down the staircase, unsure of what to do.

With a cry, Sherlock pushes Moriarty off the railing of the stairway, but at the last moment Moriarty twists and grabs him, too, and the two of them plunge to the lower level below.

John's breath hitches in his throat; he rushes down to the two prone forms, beholds the cracked skull in Moriarty's head and the broken nose in Sherlock's; with a trembling hand he reaches forward and touches Sherlock's nose; he closes his eyes and lets himself shine.

When the light clears, Sherlock's nose is mended, and Moriarty exists only as fragments and echoes in the dank, dark manor.

Sherlock stirs, black curls ruffling in the breeze. John swallows as Sherlock opens his eyes, taking in the surroundings, focusing intently on John.

"What did you do?" breathes the warlock, astonishment etched all over his features, and John thinks for a moment that perhaps there are still hidden facets of Sherlock Holmes that he has yet to discover.

"I did what stars do best," John replies, pulling the warlock into his arms. "I shone."

una.

He's never slept through the entire night before, John realises as he lies, still glowing, in the bed next to Sherlock; the warlock often complains about him shining too brightly for sleep, but both know they wouldn't have it any other way.

First off, Sherlock conceded that Mrs Hudson is, in fact, absolutely correct and that caring has its advantages, especially when the love of one's life is a star.

Secondly, whatever lack of heart that Sherlock had as a warlock is now fully compensated, and then some.

And thirdly, John can admit freely that he had, in fact, fallen in love with a warlock, and not come out any worse for it.

There would be time for grief and tears, for the realisation that loving a mortal was not the best romantic investment for someone who wasn't the same. There would be time for wandering alone in a wasted forest, lonelier than a starless nightfall in winter. There would be time to bury one's heart in the heart of a mountain, and to live as Queen Yvaine does in everlasting peace and sorrow. But this is not the time.

This is the time to snuggle closer to Sherlock Holmes, to engulf his entire self with ever-effusive light, and to give his heart entirely to the warlock to treasure for the rest of their lives together.

There can be no greater gift from a fallen star.