Author's Note: Guess who saw Big Hero Six! It destroyed me, so I'm coping in the only way I know how: by indulging in fanfiction and writing my own. So here goes!

Tenebrae

Prologue

It was a nightmare. A vile, twisted, unnaturally lucid one, but a nightmare nonetheless.

How could it be anything else? This was the kind of travesty that occurred in comic books and manga—a superhero origin, or the brooding team member's backstory—this brand of devastation just didn't occur in reality.

Tadashi was ready to wake up.

He closed his aching eyes and chanted in his head: this isn't real. I'm gonna wake up now. Dad'll promise there's nothing to worry about, Mom will hug me, and Hiro—he'll laugh at me, but it's okay 'cause he'll be alive and—

But then he opened his eyes and his heart descended. The earth had cracked open, making way for a portion of hell to merge with the world; the inferno raged on, roaring the chimes of death on the world and stifling the air with oppressive claws of heavy heat. Thick columns of black ascended eternally into the sky, and the stench alone scalded him, a prelude to the flames.

He had no idea where this image originated, how such a violent image could have worked its way into the darkest corners of his subconscious, biding its time to terrorize him as he slept. But it didn't matter, because it was just that: a vivid image locked away within his head, where it couldn't harm anyone else.

Just a dream, a nightmare.

And I want to wake up now.

"Tadashi, take your brother and run!"

The crying bundle had been thrust into his arms. And he'd run. Tripped, fallen. Through the smoke and flames, Hiro was gone.

And Tadashi had kept running.

Outside, kneeled over in the bitter cold as he coughed violently, realization snapped back to him piece by piece. The house—his house—was in flames, his mother had woken him up, entrusted him to get himself and his brother to safety, but only Tadashi lay in the damp road, his arms empty and a dawning horror crippling him.

Hiro. His baby brother. Trapped inside the burning building.

"No, no! Hiro—!" He choked on the blistering ashes. Once before, he'd found the crackling of fire to be a comfort during bitter winter evenings, but the mutated embers now mocked him.

Hiro is still in here. Might still have a chance. What'cha gonna do?

He didn't have the time to decide. A chorus of splintering cracks, then in a single, fluid motion, the roof caved-in. An onslaught of heat gushed over Tadashi's shivering form as the house crumpled in on itself, a series of snaps and crunches indicative of its degenerating state.

Someone was yelling, but their voice was dull through the static screech that terrorized Tadashi's eardrums. Lights were flashing red and blue against a thick backdrop of orange and black. Hands were touching him, shaking him, and a panicked voice urged him to speak.

It was irrelevant. Because Hiro was in there. He was tiny, perhaps enough that the debris didn't hit him. They could get him out.

"Hiro."

"Hiro what?"

Tadashi glanced up, startled to find a broad-shouldered man at his side, looking at him intently.

"Can you walk, Hiro?"

Hiro. Hiro Hamada. That wasn't his name.

On shaking legs, Tadashi stood up, unconsciously gripping hold of the man's thick jacket. "I-I'm fine," he murmured. "I need to go back inside." He took a determined step toward the smouldering debris, but his bones had turned to mush and he crumbled to the glass-ridden concrete.

"Can we get a stretcher?"

Tadashi peered up at him. No, he didn't need a stretcher. He was fully capable of walking; it was a misstep. And he had to walk—Hiro was inside.

"Try not to move, Hiro. You'll be alright."

That wasn't his name! "Tadashi," he muttered as loud as he dared. "My name's Tadashi. Where's my brother?"

The hand on his shoulder tightened. "Your brother?"

"My brother, Hiro. Where is he? Did you get him out?" His voice was high and his eyes stung as burning tears left tracks along soot-stained cheeks. "Hiro Hamada. My little brother. He's still inside. Did you get him out?"

"I need some anaesthetic."

Tadashi turned his head away when he was presented with a breathing mask. What were these people doing? He was fine. Why weren't they helping Hiro!?

Then someone sighed and forcefully grabbed his jaw. On impulse, Tadashi felt tempted to bite them, just as Hiro would have. The mask was pressed to his face, eliciting a distressed whine. They were wasting time!

"I got his name. Tadashi Hamada. He asked for his brother, Hiro. Did we clock in a Hiro Hamada?"

The silence dragged on for a second too long, but Tadashi felt too weak to yell at anyone. He sighed into the mask over his mouth and nose, closing his eyes as the voices blurred together into an inaudible fog.

Hiro. His baby brother. Trapped in the burning remains.

What'cha gonna do?

-0-

Aunt Cass was a permanent presence. She was there as doctors spoke of scrapes and bruises his body had sustained, and the blow to his head that concerned them.

A concussion, a doctor had said. It was minor and should heal up, but he needed to take it easy for a few weeks.

Yes, that was all fine and mighty, but what happened to Hiro? His parents? Why were those questions ignored?

As the doctors left, Tadashi was prepping himself to get up and search the hospital room by room, but one devastated look from Aunt Cass drained the energy from his body. He slumped back against the pillow, unable to blink or breathe for what felt like an eternity.

Cass sat beside him, her trembling hands gripping his own, and her once bright eyes tainted by despair. "It was an intense fire, Tadashi," she whispered, as though anything higher would shatter them both like glass. "They didn't make it."

It was a nightmare, that was all. A rare and inexplicably detailed one, but he would wake up. He always did.

-0-

The mind was tricky thing. It took delight in deceiving the owner, be it through hallucinations or irrational emotion.

Either way, Tadashi was more than ready to wake up. It had to be a nightmare, it simply had to be. How else did any of this make sense?

Sat in his new bedroom, located in Aunt Cass' home, Tadashi stared down at the object cupped in his hands. She'd bestowed it to him on the day they left the hospital; it was a final, desperate attempt to cut through his shield of denial.

It was an action figure. Hiro's prized possession. He'd snatched it up during a casual stroll through a comic book store and never let go, wailing anytime their mother attempted to prise it from his tiny fingers.

It had been partially melted, but remained in recognizable shape. Recovered from beneath a beam in the rubble of the building.

As Tadashi sat in the darkened room, twisting the misshapen lump between his fingers, he restrained the compelling urge to throw it across the room or smash it against the floor. How did it make sense? This tiny, insignificant object had survived the fire, but his baby brother couldn't ...

Because you left him.

Hiro Hamada was three years old, going on four. And Tadashi had sworn to be the best big brother Hiro could ask for. He'd every intent to uphold that promise, come hell or high water.

Their mother had entrusted him to protect Hiro. He'd failed. No, he'd run away. Left Hiro behind when his baby brother needed help. Alone, crying, and burning.

Cassandra Hamada was jolted from her uneasy sleep by the cry of pure despair that was ripped deep from her eldest—her only nephew. She ran her hand up and down his hunched back as he threw up his latest nightmare, then helped him wash up and tucked him into bed, combing her fingers through his hair over and over. Choked sobs escaped his chest, and he clung to her steady warmth as she soothed, "It's going to be okay, Tadashi. I'm here. I'll always be here."

-0-

Author's Note: It isn't all doom 'n gloom throughout. There's happiness on the horizon.