trapped underwater 

After an earthquake destroys their underwater station, six researchers must navigate two miles along the dangerous, unknown depths of the ocean floor to make it to safety in a race ...

Two sisters on Mexican vacation are trapped in a shark observation cage at the bottom of the ocean, with oxygen running low and great whites circling nearby, they have less than an hour ...

A civilian oil rig crew is recruited to conduct a search and rescue effort when a nuclear submarine mysteriously sinks. One diver soon finds himself on a spectacular odyssey 25,000 feet ...