The house at Half-Moon Bay was dark and deserted when Guerrero pulled up outside. He made a cursory sweep of the single floor building before going back to the car to retrieve the doctor. A thin line of light escaping beneath the garage door when he'd arrived had already pin-pointed the most likely place for Grimes to be holding Chance, but the heavy garage door didn't look like a promising place to enter unnoticed. His quick scout through the house had revealed an internal door that opened into the garage from the kitchen, and he reasoned that he'd stand a much better chance of opening that door without immediately alerting Grimes to his presence.

Guerrero uncuffed the doctor and pulled him to his feet, pressing a finger to his own lips to indicate that he should keep quiet. Heatly nodded and followed him into the house. Guerrero drew his gun and headed straight for the kitchen, and it occurred to Heatly that if he was ever going to make a run for it, now was the time. He dismissed the idea as soon as it occurred to him. It wasn't just the thought of what Guerrero might do to poor Mary, who was still locked in the trunk; or even the knowledge that he would face criminal charges over the way he'd mishandled Grimes' case that stopped him from running. It was the cold shame eating away at his soul that his actions were in part responsible for Grimes' descent into madness and the death of his wife.

Despite the fact that the lean physique of his youth had long since disappeared, thanks to a good twenty years behind a desk and the inevitable middle aged spread, in his heart, Heatly was still a Marine. He was ashamed that he'd let money seduce him into betraying everything he believed in, everything he'd fought for and good friends had died for.

Semper Fidelis…

What loyalty had he shown to God and country by accepting bribes to hide the extent of Grimes' deteriorating mental state? He'd told himself that he was doing the SEAL a favour by treating him quietly, that perhaps with the right treatment he could return to active duty without the unnecessary stigma of a diagnosis of a serious mental illness; but deep down he knew what he was doing was wrong. By all accounts Grimes was a good man, a good soldier, before all this happened. He had deserved to receive the appropriate treatment, to be taught to manage his condition with a little dignity, not cover it up until it ate him away from the inside. He owed it to Grimes to try to negotiate a way out of this mess without unleashing Guerrero on him. Despite what he'd said to Guerrero in the car, he wasn't entirely sure that Grimes' mind would be clear enough to use his combat skills to their full effect, and there was no way of knowing who, if anyone, would walk away from a confrontation between the two men.

Guerrero eased the door to the garage open in almost perfect silence. Heatly's view into the garage was obstructed by Guerrero himself, but he could see his face lit up in profile by the fluorescent light of the garage as he looked inside, and his stomach sank. Heatly had seen madness in many forms throughout the years; first as a Marine when he'd faced men caught up in the heat of the battle to survive, and later dealing with those who had been part of such horrific situations that their own minds twisted against them; but it wasn't madness that he saw in Guerrero's face at that moment. It was worse. He saw an iron-clad sanity, inflexible and calculating. He knew he was looking at a man who was capable of monstrous violence without being affected by it; but worst of all beneath that remained the capacity to care, and right now the one person it seemed he cared deeply about was in danger. Heatly thought of what Guerrero had said at his office: "There is nothing I wouldn't do to ensure my colleague's safety, and I mean nothing."

Heatly knew he was going to have to step in now for there to be any chance to avoid carnage, so he reached out and put one hand on Guerrero's arm.

"Let me try," he whispered. Guerrero begrudgingly allowed him to trade places with him, and when Heatly saw what Grimes had done to his friend, he was amazed that Guerrero had shown so much restraint.

Heatly barely had time to take in the sight of the blonde man tied to a ring in the floor, noose around his neck and blood oozing from his bruised and lacerated back, before he noticed the can of gasoline in Grimes' hands.

"You've served your country well, Lieutenant Grimes" the blonde man said. "That has not gone unnoticed by -" Heatly winced as Grimes threw gasoline in the helpless man's face, and Guerrero immediately picked up on his reaction.

"What the fuck has he done?" Guerrero demanded.

"Put the gun away," Heatly replied. "Please. For the sake of your friend."

"What the…?" Guerrero was hit by the smell of gasoline as Heatly stepped into the garage.

"Dr Heatly?"

"It's time for us to talk, Lieutenant Grimes. I'm here to help you decide your next move."

When Chance heard the doctor's voice, he turned his head as far as the noose would allow, and saw the doorway though which he'd entered the garage. The room beyond the door was unlit, and the bright lights of the garage made it impossible for him to see who or what lay beyond that door, but he knew that Guerrero wasn't far away. He hid his relief, and coughed loudly, partly to signal to Guerrero that he was conscious and knew that he was there, but also to draw attention to the gasoline fumes. The chances of Guerrero firing off a round and missing his target were fairly remote, but if a round ricocheted off any of the numerous tools or metal surfaces in the garage, there was always the risk of a spark that could ignite the gasoline that was still dripping from his body.

"This is a test," Grimes said. "You're here to witness my test."

"The test is over, Lieutenant," Heatly replied. "It's time to report back to base for debriefing."

Grimes seemed to consider this for a moment. Chance could see that the doctor wasn't nearly as calm as he sought to appear. His face had the greasy sheen of a cold sweat to it, and despite the open and non-threatening body language he was trying to display, Chance could see the tremors in his hands. Heatly was anything but sure of how Grimes would react, and Chance wondered what it had taken for Guerrero to get him to co-operate.

"The test is over?" Grimes asked, frowning.

"Yes. It's over. You have done very well."

Grimes nodded, seeming to accept what the doctor was telling him. "But that's the final test, isn't it? To see if I complete my mission?"

"There is no mission, Grimes!" Heatly said, his fragile façade cracking as fear crept into his voice. "It's over! It's all over!"

A peaceful, almost serene look spread across Grimes' face, and for a moment Chance dared to hope that the doctor's words had pulled him back from the precipice; but then, almost as if in slow motion, Grimes planted one foot on Chance's chest and shoved. Chance managed to stay on his knees, but it really didn't matter; the noose snapped tight around his neck, the cord biting deep into his throat as his airway clamped shut. He dragged himself upright, but it was no use, the knot had pulled too tight and his hands were still bound behind his back, so he had no way to even try to loosen the knot.

Heatly tried to rush to his aid, but Grimes caught him by the shirt and punched him three times to the face in rapid succession, still with that eerie look of calm on his face. He probably would have beaten the man further, but he was distracted by the figure that appeared out of the darkness.

Despite Grimes having lost touch with reality, he still had the presence of mind to draw his knife when he saw Guerrero moving towards him. Guerrero had anticipated this, and rather than rushing in, he forced himself to hold back and focus on the fight rather than the sight of Chance slowly having the life choked out of him.

Flecks were already beginning to cloud Chance's vision, but he thought he saw the metallic gleam of a knife in Guerrero's hand before his sight began to fade away. His head seemed to grow too heavy to hold up, and as it lolled backwards he thought, That's good. Guerrero is very good with knives.

"Help him," Guerrero said to Heatly.

A flicker of anger passed across Grimes' face, and his attention momentarily shifted back to where Heatly was struggling to his feet. Guerrero took advantage of the distraction and struck at with a punishing combination of blows that should have ended with a slash to the side of Grimes' neck, but as soon as the attack began, his attention snapped back to Guerrero. He countered his moves with a rapid series of blocks, before trapping Guerrero's arm against his body and raking his blade across Guerrero chest, leaving a long, but largely superficial gash, and shoving Guerrero away.

The move threw Guerrero for a second. There were only three rules when it came to a knife fight: expect to get cut; finish it fast; and fight to kill, because if you didn't, the other guy sure as hell would. There was nothing wrong with the speed of Grimes' movements, but the intent to kill, the will to strike the critical blow was not there.

There was no time to think. Chance was not breathing. How much time had passed since Grimes had kicked him? Thirty seconds? A minute? Chance was already losing consciousness. Had it been longer than that? How much longer did he have before it was too late?

Grimes kept looking at Chance, then Guerrero, then back to Chance again. Guerrero's blood was boiling, and every second was pulling Chance further away from him. Heatly had been right, Grimes still had the instincts and training to fight and kill, but for some reason he was holding back.

Guerrero tried again, throwing a flurry of punches, kicks and strikes at Grimes, but again he countered every move, deflecting what should have been lethal strikes into mere flesh wounds, scrapes and nicks. He was good, but not that good, and if Guerrero could just make himself focus on the fight instead of the colour draining from Chance's face, and the fact that he was still not breathing, he could have made short work of taking Grimes down. But Chance's lips were now turning blue, despite Heatly's attempts to try to loosen the cable wrapped around his throat. If there was just more time…

Grimes seemed content to fight Guerrero off without making any attempt to finish the fight, and the way he kept throwing in wild, pointless slashes made it feel like he was just taunting him. In a sudden flash of clarity Guerrero understood what the SEAL was doing. He had no intention of even attempting to end the fight with Guerrero until Chance was dead. He'd been rambling on about some kind of test, but holding Guerrero off, keeping him occupied whilst Chance was strangled to death was his real objective. That's why he kept looking back at Chance; his life was just a way of keeping score. As long as Heatly's efforts to help Chance were ineffectual, he didn't bother to intervene; Guerrero was the real threat to the outcome of his "test".

Guerrero could see that if he didn't step in to help Chance immediately, it wouldn't matter what the outcome was with Grimes. So, as it had done more times than Guerrero cared to remember, it came down to doing what the other guy wouldn't, to pushing beyond the limits of what even a seasoned fighter might expect.

The exchange of blows was so fast that Guerrero was running on almost pure instinct, but he forced himself to push Chance from his mind and focus on finding the opening he needed. When the moment came, he almost missed it. His instinct was to deflect Grimes' blade away from himself when he went to make another of those infuriating slashes against his abdomen, but he caught himself just in time, and deflected the blow downwards and slammed his left leg onto the blade, burying it to the hilt into the flesh of his outer thigh.

There was a split second delay as Guerrero's nerve-endings took a moment to register the bone-jarring pain of the seven inch blade impaling his leg, but the adrenaline surging through his system at least kept him on his feet. Grimes seemed to be having trouble keeping up with events, and was trying to pull his knife free but the muscles in Guerrero's thigh had clamped down on the blade, making it next to impossible to pull it out. His face crumpled into a look of bewilderment as he kept tugging at the knife with both hands, seemingly unable to understand how it had got stuck, and Guerrero took advantage of his confusion and stabbed repeatedly at the undefended area under his left arm.

The look of confusion was replaced by one of surprise on Grimes' face as he stumbled sideways under the force of the attack, and Guerrero made one final vicious slash across his throat as Grimes slumped to the ground, his eyes wide with disbelief as he bled out onto the bare concrete floor.

Guerrero ditched his knife and scanned the array of tools hanging on the wall over the workbench, before grabbing a set of bolt cutters. His injured leg was stiff and next to useless as he dragged himself across to where Heatly was still trying to dig the cable out of Chance's neck.

"Hold him up!" Guerrero ordered, and the doctor did his best to hold Chance upright as Guerrero cut through the knot as close to Chance's neck as he could.

It seemed to take forever, but finally the cable gave way and Chance slumped back awkwardly into Heatly's arms. Guerrero didn't waste time trying to free Chance's hands and feet from where they were still tethered to the ring in the floor; the only thing that mattered was making him breathe. Guerrero dropped to the floor beside him and used the bolt cutters to work away at the remains of the knot until the cable finally fell away. He felt for a pulse, and it was there. Slow, but definitely there, despite the fact that Chance still wasn't breathing.

It wasn't the ideal position in which to perform mouth to mouth; Chance's limbs were tangled beneath him, but Heatly supported his head as Guerrero tipped it back, pinched his nose shut and covered his mouth with his own, forcing air into his lungs.

Guerrero was oblivious to the pain in his leg as he poured every ounce of strength and will power into bringing Chance back. There was little resistance as he forced the breath back into his body, and his chest was rising and falling, so it seemed that at least his airway had only been squeezed shut, not entirely crushed.

It took both an eternity and only three breaths before Chance gave a weak cough and began breathing on his own.

"Chance! Chance, can you hear me?" Guerrero asked, holding his face in his hands. "Open your eyes, dude…"

His eyelids started to flutter, and he tried to groan but the sound caught in his throat and turned into a dry, hacking cough.

"Just shut up and concentrate on breathing, okay?" Guerrero said with equal parts relief, affection and exasperation.

Chance opened his eyes and looked up at him. It took a second for him to focus on Guerrero's relieved and blood splattered face, but as soon as he did, his face broke out in a wide grin.

Guerrero smiled back at him and mutter an affectionate "dude" just as Chance's eyes rolled back and he passed out.