"It used to be thought that the events that changed the world were things like big bombs, maniac politicians, huge earthquakes, or vast population movements, but it has now been realized that this is a very old-fashioned view held by people totally out of touch with modern thought. The things that really change the world, according to Chaos theory, are the tiny things. A butterfly flaps its wings in the Amazonian jungle, and subsequently a storm ravages half of Europe." ―Neil Gaiman, Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch

Chapter 1: The Butterfly

One can never know what actions determine your destiny, or changes it. For Billy Hargrove the thing that changed the entire course of his life was one simple action. Billy, of course, would never know that his entire short life and death would be changed by this one action. He went to get another drink from the kitchen, in doing so he saw through the window his little annoying step sister riding off on the back of some random boy's bike. Billy cursed, ran to her room to make sure he wasn't hallucinating, punched her door when he found her room empty and then booked it to his keys. By the time he made it to his car Max was disappearing around the corner. He turned off his music so he could hopefully catch up to her without her realizing he was following so she didn't hide.

He felt his stomach drop and the cold sweat on his palms was a familiar sensation. The dread he ran through his like an adrenaline shot as he drove around, catching glimpses of Max on the bike just enough to know he was going in the right direction but not enough to confidently cut them off. Billy didn't want to have to deal with the consequences of his father catching him not minding the little brat that had taken over his life. Billy lit another cigarette to mask the bitterness on his tongue that came when he thought of his father. Max was his responsibility, his burden, his father never let him forget that because god forbid those two actually fucking parent.

As the sky darkened Billy finally caught a glimpse of red hair on top of an abandoned school bus in a junk yard. Billy parked his camaro then got out slamming the door shut behind him he yelled, "Max get your skinny ass over here! What the fuck were you thinking sneaking off like that?!"

From the top of the bus he saw the wide eyes of Max and the dipshit that she ran off with staring down at him. They didn't move and then out of the bus came Steve fucking Harrington with a fucking spiked bat. This pissed Billy off even more because what was his little sister doing with…three…boys and one of which was way older. "What the fuck are you doing with my sister Harrington?!" Billy asked his fist clenching as he looked at the bat in Steve's hands.

"Look we don't have time, get in the bus Billy," Steve said gesturing with his shoulder as if this was normal.

"No, You are gonna tell me what the fuck you are doing right now Harrington before I beat your face in," Billy threatened.

"Get in the Bus Billy," Steve said as Billy heard a weird howl behind him.

"Answer the question Harrington!" Billy demanded.

"BILLY!" Max screamed above him sounding terrified, "GET IN THE FUCKING BUS!"

"STEVE, 3 o'clock!" The random boy next to Max called out.

Billy saw Steve's face change and watched as he raised the bat while he ran at him. Billy brought up his fists and was ready for a fight which was why he didn't react to the growl that sounded behind him. Steve, to Billy's surprise bypassed him entirely to swing his bat at something behind him, there was a scream. Billy turned and saw the thing that Steve hit, "WHAT THE FUCK!"

Steve wasn't paying Billy any mind he was swinging at another thing jumping at them from the side, "GET IN THE FUCKING BUS HARGROVE!"

It was like his body unfroze and Billy booked it to the bus door that opened up to another boy who screamed at them, "Steve GET IN THE BUS!"

There was another meaty thump behind him and Billy heard Steve grunt as he ran in behind him. They both made it into the bus and the boy slammed the door shut behind them.

"What the FUCKING HELL IS THAT?!" Billy demanded as Max and that boy dropped into the bus from the hatch on the roof.

"FUCK, Dustin I thought you said there was only one of them!" Steve yelled as he grabbed a metal panel from the window and braced his feet against it to hold the door to the bus closed.

Billy was regretting that he left his crowbar in his fucking Camaro.

The bus shook as those things slammed into it and Billy screamed, "WHAT THE FUCK IS GOING ON?!"

Steve said "Not the FUCKING time HARGROVE!"

The door buckled and Steve slammed his bat into the thing that charged inside. The kids screamed, one of the kids was on a radio screaming that they were gonna die, Max backed up to the ladder and Billy was looking around for a fucking weapon. The roof pounded as one of those things jumped onto the bus, Billy heard Max scream and he was moving before he processed what was happening. He brought up his fists as he tossed Max behind him.

Steve was running up behind him, "Outta the way!"

Billy looked up at the monster above him and screamed "COME ON!" with nothing but his fists up. The monster's face opened up as it screamed down at them and then suddenly it looked away. Defying all fucking logic it howled to the sky and ran off. The bus shook as they left their howls and growls echoed. Steve made a shushing gesture with his mouth as he cautiously made his way to the door the kids following him like ducklings. Billy took up the rear heart pounding and he clenched his fists to keep them from shaking.

"What is happening?" The boy behind Steve said.

Steve had his bat up and was ready to swing at a moment's notice and the chill in the air reminded Billy that he was very exposed wearing nothing but his work out gear. He wanted his crowbar. "Maybe Steve ad Billy scared them off," the other lispy boy said hopefully.

"No way," Steve said as he rested the bat on his shoulder, "They're going somewhere."

"That's fucking peachy and all but will one of your god damn people tell me WHAT THE FUCK IS GOING ON?!" Billy yelled with frustration, "What the FUCK was that thing? Why the FUCK are you guys waiting for it in a FUCKING junkyard. WHAT THE FUCK?!"

The kids started talking over each other in a jumbled mess Billy couldn't make any sense of and in his frustration he yelled, "Shut the FUCK UP, Harrington, EXPLAIN!"

Steve groaned and sighed rubbing his hand down his face, "That…dammit…that is a very long story and I don't even know where to start. But we need to follow those things, before we lose their trail and we don't have time."

"Fuck," Billy said as he went to his Camaro and grabbed a jacket and his crowbar out of the trunk. "Get in the fucking car then dipshits."

They looked at him like he was crazy, "They are heading to the train tracks, can't exactly drive on those." Steve pointed out.

"Take a walk on the wild side Harrington, you never drive on tracks before? Besides this way we are not out in the fucking open while tracking those shits down. And you can explain What the Hell is going on in this town," Billy slid into his driver's seat and then looked at the four of them standing frozen. "WELL? Get in the fucking car!"

Max startled first and then led the kids into the back seat and Steve sat in the passenger with his bat in his lap. Billy did what he did best, he drove his car keeping an eye out and catching glimpses of those fuckers as he drove. Billy heard Steve sigh and groan at the same time. "The short of it is, the government was experimenting on a little girl with powers, that girl opened a portal or some shit last year that unleashed a giant monster."

"Demigorgon." The lispy boy interrupted.

"Demigorgon or whatever, it was killing people and abducting people last year. The Demigorgon was like 3 times bigger than those things." Steve continued.

"Demidogs," Lisp interrupted again.

"Demidogs, Jesus, stop interrupting! Anyway, last year I fought the Demigorgon with Nancy and that little girl ended up killing it. She disappeared. Dustin here," Steve pointed at the lisp kid, "Found one of those demidogs by this house and decided to keep it as a pet."

"First of all, HOW the FUCK did Dustin was it? See one of those fucking things and think…oh yeah I'm bringing that thing home as a pet? DO you have NO FUCKING SURVIVAL instincts in you AT ALL?" Billy interrupted.

"First of all Dart was tiny little thing when I found him, he has molted 3 times since I have had him." Dustin defended.

"Molted?" Billy asked confused.

"Shed his skin to make room for more growth." Dustin explained.

"Well when is he gonna molt again?" Max said worried.

"It's gotta be soon, when he does he's gonna be fully grown or close to it. So will his friends." Dustin said.

"When he does he is gonna need a lot more than just cats." Steve said humorlessly.

"Wait, cats! Dart ate a cat?!" The other kid said.

"No, what NO." Dustin was a little too quick to deny that.

"What are you talking about he ate mews?" Steve said as he pointed Billy to a side road off the tracks that led up a hill.

"Mews, who is MEWs?" Max asked confused.

"It's Dustin's cat." Steve said.

"I knew it! You kept him!" The kid said angrily pushing Dustin into the back of his seat.

"No, No I, No I…HE missed me and he wanted to come home," Dustin defended weakly.

"BULLSHIT!" The other kid yelled.

"I DIDN'T KNOW HE WAS A DEMIGORGON!" Dustin defended.

"So now you admit it!" kid yelled back.

"Guys who cares? We are here now," Max said trying to get them back on track.

"I CARE! You put the WHOLE party in Danger! You broke the rule of law!" Kid said.

"SO DID YOU! You TOLD a STRANGER and now because of YOU TWO PEOPLE KNOW!" Dustin yelled back.

"A STRANGER!" Max said offended.

"SHUT THE FUCK UP ALL YOU LITTLE FUCKERS! That little dipshit's questionable choices in pets aside what the FUCK does all this have to do with this?!" Billy yelled frustrated.

"Hey guys," Steve interrupted.

"You wanted to TELL her TOO!" Kid said.

"BUT I DIDN'T!" Dustin shouted.

"GUYS!" Steve shouted getting all their attention to the roaring they could finally hear as Billy parked his camaro and turned off the engine.

The other kid leaned into the front from the back seat with his goggles up looking at where they heard the growls and howls, "It's the lab. They were going back home."

"What fucking LAB?!" Billy said.

"The Lab they experimented on the little girl is over there, the portal to that monster place is there," Steve answered.

"Like that was helpful." Billy said pissed, "Again why the fuck are we following monsters in the dark?"

"Yeah, why are we headed towards that?!" Max chimed in with agreement.

Steve looked at the both of them, "Look, we can either do this ourselves or trust the government that decided to torture a little girl into opening a portal to this hell dimension to stop it. I don't know about you but I would rather face whatever the fuck this is head on. Not wait for these things to overrun everything and get us hiding in our homes like cowards. We are in this now, you can back out but I am going."

"King Steve finally makes his appearance, now I get what everyone is talking about," Billy said as his engine roared to life and he sped off in the direction of the lab. "I for one am not a fucking coward, let's do this stupid fucking thing."

Steve grinned at him and said, "Well nice to have back up besides little kids. When we get to the lab you three are staying at the gate while Billy and I check it out." The three of them started to clamor all over each other talking all at once trying to protest. "NO! Enough, you three will be zero help actually fighting these things off and will just be distractions. You ALL are staying at the gatehouse and hunkering down. Billy and I will go in to see what the hell is going on."

At the gate there was no one guarding it, the booth was empty. "Well, that's fucking promising." Billy said sarcastically.

"This is why I said WE needed to do this, OUT munchkins, Dustin get this gate open and close it behind us! That way if any of those monsters get past us or we go down at least there will be a gate to slow them down." Steve said as he kicked the kids out of the car.

The moment the gate was wide enough Billy peeled out and through it. Steve kept his eyes open and saw Hopper's truck in the parking lot, "Shit."

"What?" Billy said looking from him then back to the road paranoid.

"The Police Chief is in there." Steve said.

"How the fuck you know that Pretty Boy?" Billy said as he slid to a stop in front of the doors. They got out quickly; Steve held his bat at ready hearing screams and growls as they ran through the doors.

"We're friends? I guess? He was caught up in what happened last year, we're friendly at least." Steve said.

Billy got through the doors as crowbar in hand, and then the power surged as the lights shut down. They heard the sound of the locks clicking into place against the backdrop of screaming, howls and growls. "Well…this is fucking great…now we gotta fight these fuckers in the dark." Billy sighed as he moved closer to Steve.

They came from different directions and through silent agreement the two of them turned to their targets. Billy clutched his crowbar and Steve his bat. The screams and the gunshots covered the sounds of the two demidogs they were fighting. The screeches and howls were deafening. When Billy swung at his target the second time the curved end of the crowbar got stuck and so he struggled to keep the things snapping face away from him.

Steve was struggling behind him and from the meaty impacts Billy thought he was having better luck at keeping his off him. He screamed as the things front claws met his left leg as it struggled half in the air stuck to his crowbar. It felt hot and then cold. Billy could feel the blood running down his leg and filling up his shoe. His grip on the bar was slipping and he thought maybe this was how he was going to die.

Then the bat came swinging in with a huge gross thump the thing slumped down dead. Billy hissed as he slammed the thing down and wrenched the crowbar from where it was stuck, "Next time I'm bring a machete…Thanks Harrington." Billy hissed as he looked at the damage to his right leg. "Fuck," he hissed as he pressed on the claw mark hoping he wasn't going to need stitches.

Steve dropped down looked at his leg and groaned, "Maybe next time wear some pants. Come on, there is a supply closet right there and I don't want to be out in the open with you bleeding." Steve helped him to the closet and then kneeled down again to look at his leg. He got up to look around the room and finding nothing to stop the bleeding he whispered "fuck." Before taking off his jacket and then his shirt.

He gripped the end of the shirt with his teeth and ripped it into strips in front of Billy's disbelieving eyes. Then he wrapped up the leg with his makeshift bandages and tied them tight making Billy hiss as the pressure helped to numb the stinging pain. "You're a real stand-up guy you know that Harrington…give a man the shirt off your own back type." Billy teased as the building suddenly went eerily silent.

Steve cursed under his breath as he pulled his jacket back on, " Shit." He muttered as he peeked through a crack in the door.

Billy pulled himself up and leaned over Steve from behind to see through the crack as well. There was four of those things swarming over the two dead ones and they were prowling the hallway leading to their closet. Steve very gently closed the door and leaned back sighing. Billy froze as Steve leaned back into him, but Steve didn't seem to care as his face screwed up in frustration.

" Until they leave… we can't make a move." Steve whispered and knocked his head against Billy's chest making him move back. Billy made room and they both slid down to sit side by side in the cramped space.

For what seemed like forever they sat there in tense silence clutching their weapons in their laps and not saying a word. "So, what's the deal with you and that Wheeler chick?" Billy whispered to break the silence.

" What?" Steve whispered back in disbelief.

"This waiting around bullshit is boring, so, Wheeler?"

"I don't know," Steve whispered back tilting his head back against the door.

"You don't know?"

"Its complicated…at Tina's party she said our relationship was bullshit and that she didn't love me. We fought after…I was being a dick…I went to apologize when I ran into Dustin. The roses I got her are probably dead by now."

"Wow…you're really strung out by that chick."

"Shut up Nancy is special…you don't get it."

"You're right. I don't get it…didn't she run off with that bulldog looking mother fucker, camera dude?"

Steve went silent with a pained look on his face. "Last year, when all this was going down. Nancy and Jonathon were figuring it all out on their own. I just found them in the last bit of it…kinda like you. I walked in on an attack and I saved them. But the thing is…going through it together…they had a bond I couldn't touch. I thought when we got together…that it didn't matter…that she picked me and that was enough."

"Well…whatever fucking happened last year…that bitch made her choice."

"Don't call her that." Steve rebutted weakly.

"What…a bitch?" Billy smirked, "What else do you call a girl that fakes a relationship with someone, lets someone fall in love and then says its all bullshit?"

"She didn't fake it…we were real…" Even to Steve it felt like a hollow reply.

"No man. YOU might have been real with her but she wasn't with you. That is a grade A bitch move." Billy said firmly. He hated that. Disloyalty was disgusting. Billy was always upfront on not having expectations on people when they hooked up and not letting people expect anything from him. His father was like that Nancy Bitch, letting people fall in love with a hollow mask while she was not invested at all.

Steve got up and opened the door a bit to see if the demidogs were gone. There was one lingering, but Steve was sure they could handle it…the thing was it would have to be fast if they didn't want the others to come rushing in as backup. Steve had no idea where the others were. Billy didn't comment on Steve being evasive, figuring it was probably too fresh and the guy was still having delusions that Nancy Bitch was going to come back to him. Steve closed the door gently and gestured for Billy to get up.

Billy got onto his feet, his left leg was stiff, tight and painful. However, it was useable. Billy nodded at Steve, and they made their way out the door towards the Demidog that was turned away from them. They stepped slowly the slow alarm ringing above them and covering the noise of their steps. Steve and Billy's eyes met; in silent agreement each went to a different side. Then they swung down hard both at the same time at the bas on the neck before the Demidog knew they were there.

There was a short howl as it died but thankfully it was covered by the droning of the alarm. For a moment they were still waiting, waiting for the sound of more, and they both let out a breath they were holding when none came. They crept along the hallway, walking cautiously, and eventually found a stairway with two downed security people. They were dead but that wasn't what caught Billy's eyes. It was their belts with walkies and guns.

Steve nodded and took over as lookout and Billy worked on getting the belts off. The guns would be too loud. He knew that he would be trying to avoid using that as much as possible, but it was better to have more weapons. He really needed a machete.

Billy got one done and put it on really quick putting the walkie's earpiece in then going down for the second one. Billy didn't even wait for permission and put it on Steve without even asking, preferring to get this over with fast to get off the floor. Steve helped him up and then they were off again, cautious. Then there was a light flashing in their eyes and Steve was pushing him back again bat raised.

" Hey, hey, hey…I'm Bob…I'm not gonna hurt you." The older man whispered at them hands up and flashlight shining above his head. He was overweight and had on blue scrubs. Billy was tense, if this was one of the fuckers that brought this upon them he might very well swing the crowbar that was clutched tight in his hands.

" Joyce's Bob" Steve whispered back untensing when the fat guy nodded.

" Where are they? We're here to get you out." Steve hissed looking around and keeping his head on a swivel.

"They are two floors up, I need to get to the basement to flip the breakers and get the doors unlocked. We can't get out without that." Bob replied nervously. Billy noticed the way he had a hard time juggling the flashlight, walkie and gun in his hands.

"Is Hopper with them?" Steve asked. Bob nodded and Steve sighed nodding. "Then we'll go with you."

Bob looked like he was going to protest but Steve bypassed him to go down the stairs with Billy hot on his heels. They were in this together. Bob had a look of frustration on his face as he led them down the stairwell and into the basement. The man was jumpy and as they were making it through the basement and when the steam hissed out of one pipes it had all three of them tense ready to fight.

They made their way over dead bodies while Bob ran to the breakers and started flipping switches. The lights flickered on above their heads and Billy breathed out relieved that they didn't have to fight in the dark anymore. Their walkie's crackled in their ears.

"Steve is that you?"

Steve brought his walkie up from his pilfered belt, "Yeah it's me Hopper."

Bob ran to the computer to type away.

"What the hell are you doing here?"

"Saving your asses looks like." Steve replied flatly.

Bob finished up and Billy was leading them out.

"Wait! There is one in the east stairwell!" A new voice called out and Billy was booking it adrenaline washing away the pain in his leg. He had been in a bitch position all night getting his ass saved by Steve and now his blood was pounding in his ears drowning out the protests. Before the thing can react, Billy is on it, hitting it over and over and over. Until the red faded from his eyes and the blood rushed away from his face allowing sound to trickle back in.

"Shut up Hopper! We've been killing these things all fucking night! Get them all out, we got Bob, we'll meet you by the front doors." Steve was dragging Bob behind him and booking it.

"Come on Billy! The others definitely heard that one! Get your ASS MOVING!" Steve ran up the steps not caring about sound.

Bob was huffing and puffing behind them and Steve let him go to lead the way with his bat at ready.

The screeching and howls rang out and Steve pounded through the doors with the two of them hot on their heels. Billy started to slow down as his leg acted up and to his mortification Bob grabbed his arm to help him run. They made it through the doors and into the lobby where a group was waiting for them. Bob had froze on seeing the woman and Billy was held hostage next to him in his grip. Steve had slammed the doors shut and the heavy thud as one of the monsters hit it was like a gong.

Just when Billy was going to shake Bob off there was a screech and the air was knocked out of him as Bob landed on top of him with a monster on top of him. Bob screamed and the woman screamed as the thing slammed its claws into Bob's side. Then there was Harrington with his fucking bat, hitting the thing off them and screaming at Billy to…" GET THE FUCK UP BILLY!"

Billy gasped as he pushed the fat bastard up and Harrington grabbed them both pulling them forward into a run as Hopper let loose with a machine gun for cover. They made it out the door and Billy hobbled to his car as Nancy Wheeler peeled into the front of the building. Which was lucky because the moment Steve was in the car Billy booked it not giving a rat's ass about waiting for the others. He needed to get to Max before those things got out.

He skidded to a stop at the gate, "GET THE FUCK IN THE CAR MAXINE!"

She drove into the back and so did her two friends. They were quick and then they were out. Billy had a hard time catching his breath and Steve was on his walkie talking to the ones following behind them.

"We're going to the Wheeler's, turn left up ahead." Steve said and Billy followed.

Man…What a fucked up night and Billy was feeling that this night was just going to get worse.