A/N: this fic was inspired by the P!nk song, "Bridge of Light." Every time I hear it, I...the feels are everywhere. The lyrics of the song are the ones written in the fic. Also, this takes place in those few horrible moments in 3x03 when Sherlock's heart stopped. Basically, it's my version of how Sherlock made himself come back to life.

Just when you think hope is lost
And giving up is all you've got
Blue turns black
Your confidence is cracked
Seems no turning back from here.

Sherlock was lost.

He knew he was in his mind palace, but at the same time, it was...not his mind palace. He knew every nook and cranny, every corridor and room, every single staircase and corner, and why should he not? He had built it from its foundation up. But now it was...wrong. It was as if someone—his money was on Mycroft—had picked up the palace and shaken it silly before setting it back in his head. None of it was in its proper place. Rooms were in their wrong places, doors were flung open, files were scattered everywhere. Passages that should have kept going dead-ended at a blank wall. Where there had been staircases, there was nothing. He wanted to scream in frustration.

I have to get out! I have to find my way back out. I can't die, not right now, he thought in panic. Death was already starting to pull down the palace. Cracks were appearing in the roof; the walls were starting to dissolve. The longer his brain went without oxygen, the longer his heart was not beating, the more he would come apart, until everything unraveled and he'd be lost in the endless oblivion. Sherlock couldn't do it. It would not stand. He would not, could not let it happen. He had to find his way back out of the palace, back to Life. There were cases that needed solving, criminals that needed catching. Death was so abysmally boring. He couldn't die now.

Sherlock turned around a corner that wasn't supposed to be there and skidded to a halt, eyes wide. The entire wall in front of him was gone; on the other side, there was nothing but a great, gaping void, eternal darkness, utter nothingness. Cracks were beginning to spiderweb out from the yawning hole, crawling over the wall and floor and ceiling. He took a step backwards, breath trembling in his lungs; sudden panic overtook him. He whirled on heel and fled from that horrid, endless void, fleeing through his jumbled-up Mind Palace, anything to get away from that terrifying nihility. As he went around another corner, he choked on a terrified gasp at the sight of more cracks, darkness seeping into the brightly illuminated corridor. No. No! Everything was falling apart. He was running out of time. No matter where he ran, it seemed, the fissures kept appearing, crawling along the walls and the ceiling. No matter what door he flung open, it was always the wrong one, it always was the rooms containing memories he'd so long ago tried to push aside and bury in the recesses of the palace.

When your feet are made of stone
And you're convinced that you're all alone
Look at the stars instead of the dark
You'll find your heart shines like the sun.

He pulled open one door only to see Mary on the other side in her gown and veil, pointing a gun at his chest. He flung the door closed again, hastily bolting away. He opened another door; on the other side, he saw his seven-year-old self, shivering and trembling in the corner of his room, bleeding from the mouth and nose where he'd been punched. Sherlock gave a little shudder, pushing the door closed again. That was one part of his life he never wanted to revisit. He felt a chill against his ankle and dropped his gaze to the floor. A long crack had opened in the floor just beside his feet, tendrils of darkness seeping outwards, curling around his ankle. He jerked away so roughly that he lost balance and fell onto his back, scrambling back away from the chilling touch as fast as was possible. Sherlock felt his breath coming faster, almost hyperventilating now, as he saw more of that hideous oblivion creep and crawl further into the mind palace. Unbidden and sudden, he had a terrible, horrible thought: I'm not going to be able to get out of here. His brain had been starved of oxygen for too long. His mind palace was crumbling right in front of him. He was going to die.

Gritting his teeth, he rolled onto his feet and started running down the corridor with the least amount of damage. If he was going to die, he was not going to die easily. He would keep searching. If he was going to die, he was at least going to die happy. As he ran for the nearest door, with a deafening crack! a great split forked across the ceiling. More of the darkness began to ooze in. It seemed to draw the very light out of the corridor, leaching out all colour wherever it touched, chilling the air as it came. Sherlock felt his hands begin to tremble, and he edged out from underneath the crack in the ceiling, backing down another corridor until his back met the crumbling wall. The faintest gleam of metal caught his eye; he turned his head.

At the very end of the hallway was a familiar door, with dark paint that was starting to flake away ever-so-slightly, the knocker that was always crooked, the old and slightly-tarnished metal letters that gleamed brightly despite the vanishing light: 221B. The detective felt his breath hitch slightly, and then he was running, sprinting as fast as he possibly could down the hall towards the door. The closer he came to the door, the warmer the air seemed to feel; the fading colours grew brighter. Slightly breathless and trembling from head to toe, he reached out and curled his hand around the doorknob; it felt warm under his hand. Taking a deep breath, he pulled the door open.

That's when love can build a bridge of light
That's what turns the wrongs all right
That's when you know it's worth the fight
That's when love turns nighttime into day
That's when loneliness goes away
That's why you gotta be strong tonight
'Cause only love can build us a bridge of light.

Light seemed to pour out of the door, streaming through the palace and curling around him like a living thing, filling him with a deep warmth that enveloped him from head to toe. Every happy memory he'd ever had—doing experiments as a child with Mummy, solving cases with John, his time in the morgue with Molly, playing the deduction game with Mycroft, verbally sparring with Lestrade, playing pirates with Redbeard—seemed to flood his mind anew, as sharp and clear as they had been the day he stored them in his mind palace. For an instant in time, either a span of heartbeats or a decade, he didn't know, but he was a part of the light, bathed in it, breathed it into every fibre and cell. It spread, flowing out in curls and spirals of colour and light, and wherever it touched, the sticky tendrils of oblivion retreated and the cracks healed, sealing closed. He followed the lights to the very edge of his Mind Palace, stepping to where it dropped away into nothingness. The shimmering brilliance spread outwards, twisting and curling together until it formed a glowing pathway through the darkness, illuminating his way.

Sherlock took a deep breath and stepped forward onto the path, following it and allowing the warmth and light and colour to lead him through the oblivion without fear.

"Doctor, there's a heartbeat. He's coming back."