Don Flack's crystal blue eyes scanned the darkened streets of New York City. He looked down on his hometown from his position crouched on the edge of the high-rise. During the day, he thought with a smirk, he would've been called out to talk himself down from this position. But at night, he was undisturbed. There. His eyes darted to the right, fixating on a small alleyway below. The corners of his mouth curled up in a smile that would have terrified the CSI's he worked with by day. In one graceful, sweeping movement he placed his hand on the edge of the building and vaulted off into the black.

He landed in an easy crouch, as though he'd jumped off a low brick wall rather than a 40-storey skyscraper. He stood with more grace than he'd ever shown with the CSI's, icy eyes seeming to glow in the night. He made his way carefully towards the alleyway, hands moving from his coat pockets to out in front of him, almost in a warding gesture. He paused at the edge of the alley, suddenly uneasy. He scowled to himself, shaking off his discomfort, before stalking into the alley, hands outstretched, fingers flexing.

Don listened carefully, his head tilted to the side, eyes scanning the darkness around him. A black shape exploded out of the darkness, screeching wildly, catching him off guard. It cannoned into Don, sending him careening into a dumpster. His head thumped into the dumpster, making him see stars for a second. Don shook his head, fighting off the dizziness, his lips pulling back into a snarl. He kicked out, connecting with something fleshy. The thing shrieked and stumbled back. Don moved forward, eyes cold, flinging both hands out as though he were passing an invisible basketball.

Globes of fire shot from each of Don's outstretched palms, icy blue like his eyes. They hit the thing in the chest, engulfing it in flames. Don watched impassively as the creature wailed; the sound unheard by human ears. He clenched his fists, shaking his hands to get rid of the tingling in his palms. He leant against the dumpster, eyeing the creature writhing in agony before him as though it were no more interesting than the stock prices in the Times. Tapping his foot impatiently, he waited as the creature gave one final, shuddering scream, before collapsing into a pile of ash. He nudged the ash with his toe, before nodding calmly, satisfied the thing was dead. With no further ado, he shoved his hands back in his pocket and walked home, sighing as he watched the sun rising over the skyscrapers. He wouldn't be getting any sleep this time.

Don yawned, rubbing his eyes, as he made his way towards the crime scene. He nodded to the patrol officer that lifted the yellow tape for him. Pulling all-nighters was getting harder and harder. He scanned the area, catching sight of Danny Messer, altering his stride to walk over to the blonde CSI.

"Flack! Pay attention, man!" Danny snapped at the taller detective.

Don jerked at the exclamation, halting his foot in mid-air, inches from Danny's hands which were curled protectively over his evidence bags. He gave the CSI an apologetic shrug and a sheepish smile.

"Sorry, buddy," Flack apologized, barely hiding a yawn, moving his foot to the side.

"No problems," Danny answered, "You missed. Hey, man, what's with you today? You look like hell."

"Don't you say the nicest things," Flack griped, before his face softened slightly, "I'm good, didn't sleep much last night, that's all," he scowled as his pager beeped, then sighed as he read the display.

"Mac," he replied to Danny's questioning look, "Triple homicide in Central Park," he groaned slightly, rubbing his face.

Danny grinned, "Get some coffee in ya, you'll be fine. You better pull your head out 'fore you work any of Mac's scenes though. Serve and Protect, an' all," he teased.

Don gave him a small smile before flipping him the bird and heading back to his patrol car. Sliding into the driver's seat, he snorted wryly. Serve and Protect? Danny had no idea. He protected the streets as a cop by day, protected them as a hunter by night.

"You sound like a crappy superhero, Donny," he mumbled to himself.

It was true though. Hunting was what he did. It was in his blood, just like being a cop was. He grinned wryly. It was just unfortunate that they were both in his blood. Conflicting interests? Hmm… no… really? Almost every night, he worked the streets, watching over the city-that-never-slept.

"Worked the streets? Great, Donny, now you sound like a rentboy," he muttered dryly.

Pulling up at the crime scene, he parked his car and hopped out. He yawned widely, then schooled his face into a mask of professionalism. He nodded to Mac, before turning to the patrol officer, looking for an explanation. It would be so much easier if he could be either a hunter or a cop. Not both. A wry smile curled at the corner of his mouth. Like that would ever happen.

There were things that went bump in the night. And it was his job to bump back…