He felt his hand slip free and saw the terror in Gary's widening eyes as he fell away, the entire sequence playing out in slow motion. He slid across the angled rock face, the steep and sheer slope preventing him from getting any toehold with his climbing shoes, the normally tacky climbing gloves seeming as smooth as glass as he scrabbled at the stone. His helmet lamp illuminated a broad triangle of rapidly accelerating ground as the face of his climbing partner disappeared above him. After another couple seconds he crested the lip of the underground canyon they had been tracing, and Gary's face disappeared for the last time.
John felt his body tumbling in the darkness, his light swinging to and fro wildly as he twisted and turned in the air. He pondered trying to get control of his body and his descent, but ultimately gave the effort up as futile. With the light from his helmet being his only source of points of reference, he was having enough trouble just getting his bearings, trying to estimate how much longer he had to fall. No one really knew how deep these caverns went, and his team was supposed to be one of the first in-depth surveys of what had been playfully dubbed "the anthill" due to the complexity of the system of tunnels and caves.
The eerie part was the silence. It enveloped him, calling attention to the pounding of his heart as John continued to fall. This deep underground there was nothing to create ambient noise, no breezes or bird calls, no noise from traffic passing by. John was forced to focus on his body as he fell, anticipating the impact below. He felt oddly calm, perhaps due to the shock of the fall, or likely because he hadn't accepted his impending death yet. Somewhere, deep down, he knew someone would be able to rescue him.
The impact came suddenly, his legs smacking hard against a sloped rock face. His tumbling arrested immediately, and he found himself sliding once again down a steep rock cliff - the right side of his body leading his way into the depths. He continued to slide for a few agonizing seconds, his climbing gear taking the brunt of the impact, before he felt rock rise up against his back. He bounced back and forth between the two spaces - broad horizontal motion diminishing slowly as the two walls closed in on him. Each impact slowed him slightly, until finally he came to a stop. He was wedged tightly between two rock faces.
John laughed, and exhaled deeply in relief. As he did so, his body slid a couple inches farther down - his chest becoming more tightly wedged in the rock. He tried to move his arms, but each change of position brought his body even farther down into the chasm, his flattening muscles providing more room for his body to fall. Before long he was unable to move - his chest wedged tightly between two rocks, his head at an awkward angle as his helmet caught on a small ridge, his arms unable to come to his rescue. The pressure on his body was immense, and seemed to grow as he realized how effectively he had trapped himself.
With the rock pressing in mercilessly from both sides, he wasn't even able to scream.