It began to hiss, and the hiss rose fast, becoming a noise like escaping steam, and with it came heat rising higher fast.

“Drop to the floor.”

She came down beside him. “We’ve got to pull out.”

The heat was becoming intolerable. Mark wanted to turn and run, but that could not be. One had to die as a distraction so the other could reach the bombs.

He threw himself on the creature, slashing carefully, going for the abdomen. In an instant, he was enclosed in its claws and the touch of its skin was burning him, and he threw back his head and screamed away the agony so that it would not make him lose control of his actions.

Gina cut into the forearms, trying to free Mark, but she hacked and hacked to no effect.

“Get around it! Go!”

“I can’t!”

The choice of dying so that she could pass was no longer available. He had to win this. But the knife was growing too hot to hold. The skin of the thing felt like hot irons.

But then the knife penetrated, and he cut as he had never before cut, his arm a furious piston. He wished for a Metal Storm, but nothing like that was here.

Then he was flying through the air, bouncing against the ceiling, hitting the floor. He rolled and Gina was there immediately, slapping at the fires in his uniform.

The creature had backed a distance down the tunnel. Still blocking it, though.

He looked down the tunnel at the darkness that was their enemy, a clotted shadow now, completely filling the tunnel. No way around him, no way through him, to the bombs behind him.

“Mark?”

“What?”

Gina pointed at the wall behind them. He saw it then, also, the faint flicker of a light along the tunnel. A moment later he heard sounds, the whisper of clothing.

The flickering, a faint red, became more distinct.

“Infrared,” he said softly.

“We’re trapped,” Gina whispered, her voice little more than an extended breath.

“We have to continue on mission.”

She grabbed him, her eyes wide and wild. “We’re going to die here. We’re going to fail!”

Without warning, the creature came swarming back up the tunnel.

Now they ran, their only hope to somehow break through the detachment of generation-three hybrids that were coming on them from behind. They ran and they flew, leaping up, forcing themselves through the air, racing, shouting in pain as they scraped first one side and then the other.

Ahead, the tunnel made a sharp turn, and they both slammed full speed into the wall. Mark saw flashes behind his eyes, was for an instant dazed from the impact—then turned and leaped ahead—and saw standing in the middle of the tunnel a human woman in full battle dress.