A/N: So, I promise that I haven't abandoned my other story. I'm just having a little bit of trouble keeping the muses happy. Especially when ideas like this jump in and won't leave me alone. I don't own Chicago Med, Chicago PD, or any other known entity. Story and chapter titles come from the song, "In Our Darkest Hour" by Phantom Planet, which I also don't own. I started writing this before this season started, so there have been some new adjustments since the crossover. This story does take place in the future. I hope you guys enjoy this one, and please review. :)

Prologue: It Started Today

It started innocently enough.

A brief spark, an arc between two broken circuits. A normally innocuous flash that led into something more. A flicker of a flame, a few wisps of smoke. Easily manageable, until…

Until it wasn't.

The smoke grew from a few wisps into a cloud, spreading out across the ceiling and into a darkening haze. That was the first indication they had that something was wrong. The alarms came next, distant in nature and garish in sound, the strobe lights cutting through the haze and making the floor seem like a dance club instead of a ballroom.

The screams began shortly after the alarms as people frantically rushed to get out through the only door they knew: the one they had come in. A few others straggled to get out through other doors, but as the smoke grew thicker, the ability to find one's way became nearly impossible.

Every fearful fiber of his being wanted to run frantically and screaming out of the room as fast as he could. And yet, he stayed, trying to find others and guide them to safety.

He clung along the walls, feeling around the floor as the temperature of the room grew hotter, almost making it feel like the walls were melting around him. And maybe they were, but he was more focused on trying to help people out of the room than he was about the walls.

But, he should've been.

The smoke turned the room pitch black in every place except where the actual flames were, and he continued to creep along, hoping that he wouldn't find anyone else, because it was damn near impossible to tell which way to go. Visibility at zero, and his lungs begging for any bit of clean air.

And the screams…

The only thing that could permeate the crackle of the flames was the screams of its victims who hadn't yet made it out of harm's way. I don't know if I'm even getting out of here, he thought to himself, his eyes tearing at the thought, as well as knowing that he likely wouldn't be the only one.

It sounded like an explosion, and then the crackle of the flames turned into the roar of an inferno. The screams grew louder as he came across a small child, curled into a ball and crying in fear. He quickly grabbed her, holding her to him as he fought his way back where he came from.

Except now, he didn't know where that was.

The screams grew louder, starting to drown out the overwhelming sounds of the flames. It wasn't until he tried to move a little further and found himself trapped that he realized that the screams were actually coming from him.

The burning pain as the flames began to envelope him was almost too much to bear. He tried to make it a little further before finally realizing the futility. He used his body as a human shield, clutching the little girl under him to protect her from even an ounce of the pain he felt. It wasn't long before he thought he heard footsteps, but even that, too, faded away.

All that came next was the terrifying sound of silence.