Sam crept forward again, trying to get a better look without being seen. The scissors he held like a knife. White knuckles wrapped around and through the plastic circles so he could maximise the force of his strike.

Behind him Alice moaned softly. That was a good sign, so long as the shooter didn't notice.

The man was in no rush. He held the pistol casually in one hand while he arranged something in a bulky square bag with the other. He looked in Sam's direction every few seconds but either didn't see him duck out the way, or he was unconcerned.

When Sam looked again the man was heading for the door to the lab. He was taller than Sam, with short dark hair. He carried himself with surprising grace considering the scene he was leaving behind him. In a different environment Sam would have described him as having the air of a scholar, but here the evidence told Sam the man was a killer.

Sam moved closer to the lab door, ready to press his advantage of surprise him when he heard movement behind him.

"No, back!" he whispered, frantically waving her away.

"I can't find Alice," whispered Lyn.

Sam pointed at Alice's office. "In there. She's hurt. Hide, quick!"

But Lyn wasn't quick enough. The shooter saw her as he approached the battered door frame. The bag was slung over his shoulder, and Sam could now see it was a medical transport bag, suitable for material that required cryogenic storage. The man raised the pistol and pointed it at Lyn and then hesitated.

Sam attacked. He launched himself from his hiding place, grabbing the mans wrist and forcing his arm up. The weapon discharged. Sam's ears rang from the close quarter gunshot. He heard Lyn scream and from the corner of his eye saw her run into Alice's office.

Sam stabbed up with the scissors but the man twisted to avoid the strike. The scissors ripped through his suit lining but drew no blood. The medical bag fell they struggled. The man grabbed Sam's wrist and slammed it down on the broken glass of the door frame. Sam yelped and swore and dropped his weapon.

He tried to shove back but the back of his hand had been ripped open by the glass shards. Blood ran freely down his right forearm.

The man twisted free of Sam's weakened grip, scooped up the bag and made to dash for the exit.

Then Lyn charged into the hallway, pushing a wheeled chair ahead of her like a battering ram.

The man tripped, dropped the bag again and turned his gun on Lyn once more. Once more he hesitated.

This time Sam had him. He charged forward and locked his forearm around the mans neck and dropped to the floor. The sudden dead weight on his back pulled the man off balance and he fell on top of Sam. Sam tightened his grip, wrapped his legs around the man's waist and squeezed the air from his lungs. With his good hand he punched the man in the face, driving his knuckles into the mans cheekbones.

The mans survival instinct kicked in. He dropped his gun, pulled Sam's forearm from his throat but it wasn't enough. While Sam growled and swore, his forearm cut off the oxygen from the mans brain and he passed out.

When Sam felt him go limp he counted to three to be sure, then threw him to one side, and climbed to his feet, breathing hard.

His hand hurt. Blood and dirt and plaster dust caked his arm and back and he had picked up a hundred more cuts and scratches from rolling around on the glassy hallway floor.

But he still stood.