“Let’s go, guys. I want to be lying on a beach somewhere by the weekend.” She sucked in a breath and smiled broadly at Matt as she overtook them on the slope.

“Go, Wonder Woman. Can you carry me?” Matt chuckled as he said it, but both he and Monica increased their pace to keep up with her.

Alex quickly caught up to the team; they had made good progress. The slope was increasing steadily and though this gave them all reason to feel they were heading in the right direction, it was proving much more exhausting than before.

Alex knew their bodies were tiring but with the creature in pursuit they couldn’t afford to rest for a moment. The cave was narrowing even more but was still easily big enough to accommodate fifty men walking shoulder to shoulder and the roof was nearly out of sight in the darkness. The cold blackness of the cave meant they had relied solely on their torches and helmet globes, and now these too were wearying and yellowing into the gloom.

For several more hours they climbed, before exhaustion demanded a break. Alex turned and listened intently. Far behind them he could just make out the sound of pursuit. His electronic movement sensors were useless in a twisting cave as the density and compression waves became distorted and muffled by the airflow and cave bends. He had to rely on his extraordinary senses alone and this was still proving difficult as the creature without its shell was almost silent and now much more cautious. Alex was also beginning to think that the thing chasing them was not just some oversized prehistoric brute but had an intelligence that enabled it to learn, plan and perhaps even try and trap them.

Monica pointed out the jumble of debris on the cave floor. It was the first sign that there had been geological movement in and around the cavern for many millennia.

“Please Lord, deliver us from dead ends.” Matt was trying to inject a little levity into their situation, but he could not have crafted better words to reflect how they all felt. The thought of having to backtrack gave them all a feeling of dread. Though they had not seen or heard from the creature for some time, they could pick up the vibes from Alex, and the way he kept stopping to stare into the darkness behind them let them know that they were far from safe.

The shards of fallen rock were growing in size, with some now the size of houses. It made the trip slower as they constantly had to zigzag in and around the debris. The slope had reached an angle of about twenty-five degrees and their thigh muscles were screaming for a break. Alex quietly but firmly urged them on; he could not let them stop until they found a spot that was concealed or at least defendable.