A/N: Thanks for the reviews, follows and favorites! I appreciate you guys trusting me with this new journey, and I'll do my best not to disappoint. For plot purpose, I needed Steve gone and away from the house for a few hours so even though he may not have left his sister alone with someone he considered a threat, I hope what I have done here works.

Let me know what you think about it, reviews fuel my creativity and make me write faster!

Unbetaed, so all grammar mistakes are mine.

The first thing Steve noticed was the harsh red and blue glow of the emergency vehicles parked haphazardly in front of his house. Driving closer, he counted two RMPs, an unmarked sedan that was probably a detective's car and the CSU van along with the familiar shape of Danny's Camaro.

His heart froze at the thought that something had happened to his sister and niece.

I should have never left them alone. God, I'm sorry...

He stopped in the driveway, parking behind one of the cruisers. His hands were shaking as he cut the engine and got the keys out of the ignition, the guilt he'd been feeling for the last few hours suddenly raging back up inside him. Forcing himself out of the truck he started to walk on unsteady legs towards the front porch, his feet pounding into the ground in tune with his heart thumping even louder in his chest.

He had failed her. He'd failed her the one time she needed him the most.

One of the officers, a rookie he'd never seen before, spotted him and immediately informed him that the area was a crime scene and that he wasn't allowed inside. Steve was about to tell him to go to hell when the front door opened and Danny came out of the house.

"Danny!" he called, storming past the uniform.

The young man, obviously unaware that he was talking to the head of Five-0, made an attempt to follow him but the blond detective held up one hand, effectively stopping him in his tracks.

"Where is she?"

Danny met him at the bottom of the stairs and grabbed his arm to slow him down.

"Steve, wait..."

"She alright?" he asked, a look of sheer panic in his eyes.

Danny swallowed hard. "We don't know."

Steve flinched as if hurt, blinking in disbelief. "You don't know?" His voice came out harsher than he'd intended, and several heads turned around. "What you mean you don't know?"

"She's not here," Danny replied uncomfortably.

"Why? What happened?" he asked, searching his friend's features for clues. His throat constricted, dread quickly flowering into full-blown terror.

"Buddy, I don't think..."

"Please, Danny..." His face had drained of all color, and the distress in his expression made Danny's heart ache.

"There's a body inside," he finally admitted.

This time, when Steve twisted out of his grasp and hurried inside, frantically looking around as he moved, Danny didn't stop him, following him instead through the open door.

He found the answer he was looking for as soon as he reached the doorway.

Anthony Morris was lying on his back on the floor in the middle of the living room, arms splayed to the side. His head was turned awkwardly, lips slightly parted as if in surprise, eyes closed. Blood had pooled around him from a gunshot wound to the chest, turning the wooden flooring into a dark, deep black.

Shock froze Steve into place as he took in the scene in front of him, recalling the argument he had witnessed just a few hours before. Could it have escalated into a fight and the fight into... murder? He hadn't been away that long. What the hell had happened? Had he tried to hurt Mary again and forced her to kill him in self-defense? But why run away?

Why didn't she call, he wondered as tears started to well up in his eyes.

"DOA. There was nothing we could do for him." Danny's voice seemed to come from far away as he stared at the lifeless body of the man who had threatened to take his sister away.

"Joanie?" he asked in a whisper.

"She's alright. Slept through the whole thing. She's at home with my kids, very excited to have a sleepover."

Steve nodded, feeling the grip on his heart lessen a bit. "What happened?"

Danny glanced at him for a long moment, his eyes full of concern. "911 got two phone calls about shots fired around 1:00am. When the first unit got here, they found him like that. Front door was wide open and Mary was already missing."

Missing…

The more he wrapped his mind around this, the more he was convinced it had been an act of pure desperation.

But how?

Mary didn't have access to weapons. Unless...

"Shit," he muttered. He'd gotten out of bed without even thinking about his gun. Then his sister had asked him to leave.

Shit, shit, shit.

She was accusing the guy of something, but he hadn't been able to understand what the argument was about. Could he have upset her enough to trigger this kind of reaction?

Steve knew the answer to that question. Mary Ann McGarrett wasn't a saint, and her temper had caused no small share of trouble in the past. Half of her run-ins with the law had been caused by fights she had started, half of her bruises resulting from blows she'd landed rather than received. That of course didn't give the bastards she'd partnered herself with over the years the right to hurt her back, but that was another story.

As he wondered again why she had left without saying a word, he realized his lack of verbal response to her predicament had been just as effective as a dismissal.

He'd basically implied he didn't care if Anthony hurt her again.

That's why she'd felt leaving was the only option.

Where are you, Mare?

The thought that she was hiding somewhere —scared, alone, possibly hurt, made his stomach tighten with fear.

He had to find her.

But first of all, he had to make sure his assumption was right. And if it turned out she'd had no other choice than to kill him he would take care of it like he should've done in the first place.

Danny suppressed a sigh as he looked at his best friend. He could only begin to imagine how he felt. The only way he could help him right now was being there for him and finding out what had happened, and he fully intended to do both.

"Who is this guy, Steve?"

"I have no idea, man," he admitted, his eyes clouded with confusion and fear. "I was sleeping upstairs and the next thing I know there's voices downstairs and I find this guy arguing with my sister." His hand brushed across his mouth as he drew his brows together pensively. "She never mentioned him to me. Not once, and now I find out they have some kind of history together..."

The raw, pained expression on his partner's face made Danny's heart ache.

"He hurt her, Danny. He hurt her and I didn't even know it. I think she came back to Hawaii to get away from him and he followed her here. Said he wanted to take her back to LA." He looked at the floor, Adam's apple bobbing as he swallowed hard. "I don't know what he was up to, and frankly I don't even care. The bastard got what he deserved."

"Well, isn't that an interesting statement?" HPD Detective Jimmy Kao spoke up as he suddenly materialized behind them, followed by Sergeant Duke Lukela. "Be careful what you say, Commander. Wouldn't want you to be the prime suspect in one of my murder investigations."

Danny glared at him. "Easy, easy, Kao. No one's a suspect here."

"We'll see about that," the Asian man shrugged. "One thing I learned about cases like this, ninety-nine times out of a hundred the killer's a partner or a spouse." He took a few steps forward and slipped on his glasses, leafing through his notepad. "No sign of forced entry, no indication of a struggle. Back door's still locked from the inside."

"Why are you here?" Steve asked in annoyance. "Five-0 will take care of this."

"I don't think so, McGarrett. You're personally involved and no one on your team will be objective enough to handle this case." He glanced around, taking in the pristine condition of the room that was a stark contrast to the violent death Morris had suffered. "Do you know what happened here?"

"We had a fight."

"You and the victim?"

"Yeah." Steve crossed his arms over his chest, showing no emotion. "I was upstairs, heard my sister arguing and came down to see what was going on."

"Then what?"

"I got a little carried away."

Danny glanced at his friend's hands, noticing for the first time how red and chafed his knuckles were.

Kao bent forward to take a closer look at the body, examining the matching bruises on Anthony's body. "Point-blank shot to the heart. He was dead before he hit the ground." His eyes fixed on Steve as if to challenge him. "Looks like an execution to me. So, how carried away did you actually get?"

"Hey!" Danny warned.

"Back off, Detective. I'm just doing my job. He said they got into a fight, I was just asking if—" He saw Steve move out of the corner of his eye. "And where do you think you're going?"

"Upstairs."

"I'm not done with you."

"I don't care."

"You don't wanna mess with me, Commander." the Detective replied, his voice rising slightly. "That attitude is not gonna help you or your sister so I suggest you stay right here and answer my questions."

Steve sighed and turned around. "Look, man, all I care about right now is my sister. Let me just check if something's missing, alright?"

Kao pursed his lips, considering his request. "I'm gonna need to take you in for questioning."

"That's fine. Let me take a quick look and we'll go down to the station in a minute."

"Alright," the other man nodded, dismissing him with a hand gesture. "But don't mess up my crime scene."

Danny watched his partner head up the stairs and started after him, hoping his presence and silent support would somehow comfort him as he struggled to stand up after yet another blow. Having gone through as much crap as anyone could take, he was already worried about how much the stress of this new predicament was going to affect him.

Steve paused at the top as if to gather his thoughts, then stepped inside his sister's bedroom. It was a mess; the same mess he'd been used to since they were kids. Mary had never been a neat, organized person, and her room mirrored the same chaos running through her head. As he stood there, inhaling her scent, he felt his emotions rise up again.

Guilt eating at him, he placed one hand on the wall and closed his eyes, bowing his head. He seemed to jump from one mess right into another. Would Fate ever give him a break?

A moment later, he felt Danny's presence at his side and quickly straightened up, rubbing his tired face.

"Don't worry, I didn't touch anything."

"Steve, that's not what I-" He brushed past him and disappeared into the hallway without giving Danny a chance to reply. "Steve!"

The blond detective shook his head, discarding his reaction as a stress-induced outburst. They occasionally lashed out at each other when they were hurt or upset, said things they didn't mean and regretted it a minute later. He himself had been guilty of it plenty of times but at the end of the day, they were always there for each other.

BFFs, they'd joked.

Best friends forever.

Danny had never labeled what he and Steve had, never tried to diminish with words the bond that kept them together. He didn't need to. Steve was the most important person in his life right after Grace and Charlie, and he knew it was the same for him.

Sighing, he decided to allow him a few moments of privacy and took out his phone to send a quick text to Grace to ask if things were okay. She replied a moment later with a picture of Charlie and Joanie asleep in the racing car bed that made Danny's lips curve into a smile.

He wanted to believe Mary wasn't in danger, that Anthony had been killed by a random act of another worthless thug, something they could easily solve without long-term consequences, but he knew better than that.

"…Ninety-nine times out of a hundred the killer's a member of the family."

What if Kao was right?

He refused to accept the possibility. It would completely destroy Steve.

Walking back towards the stairs, he spotted his friend inside his bedroom. He was standing by the bed, his back to him, shoulders hunched over. Danny couldn't see his hands but he appeared to be holding something.

"Find anything?"

Steve jumped. He'd been so lost in thought that he hadn't heard him come in.

His fingers curled around the empty holster he'd found inside the drawer of his nightstand. He clearly remembered putting his gun there like he did every night before falling asleep, which meant Mary must've come upstairs to retrieve it after he'd left.

Tears welled up in his eyes, his heart aching at the thought of what his sister had been forced to endure, and he cursed himself for the millionth time for not being there to spare her all this.

"Steve?"

Danny's voice brought him back to the present.

"No," he replied without turning around.

"We'll find her."

"Yeah," he nodded unconvincingly as he placed the holster back inside the drawer.

"You ready to go back downstairs?"

Steve finally met his gaze and they shared a long look. "She doesn't deserve this, Danny," he whispered hoarsely. "Not after everything she's been through."

"It'll be alright, Steve. I promise."

Steve wished he could believe that. Nothing would ever be alright, not for a long time, but he knew how to make things at least a bit better.

In the living room, Dr. Noelani Cunha had already finished her preliminary exam and they were getting the body ready for transport. Steve saw Anthony's limp arm dangling off the stretcher as they lifted him, and once again anger threatened to take over.

He wanted to reach out and yank the son of a bitch off that stretcher, shake life back into him and ask him why he had hurt his sister, why he'd showed up right when things seemed to finally going their way and messed everything up. He had so many questions that demanded answers, answers that had died with him and that he wouldn't find until they located Mary and listened to her side of the story.

"I'm gonna need your weapon," Detective Kao stated, coming to stand in front of Steve and blocking his view of the body. "And a list of places your sister could have gone."

"Just leave her out of this."

"Are you telling me how to do my job, Commander?" the Asian man inquired, hands on his hips.

"You don't need her."

"That's not for you to decide."

"She's got nothing to do with this!" Steve snapped, drawing Danny's attention. The Jersey native put the cell phone he had just retrieved back into his pocket and moved closer.

"How do you know that?" Kao pressed.

Silence filled the room for a moment as all eyes fixed on the Five-0 leader, waiting for an answer.

Steve's gaze didn't waver as he looked at them.

"I killed him."

TBC