movie about underwater deep trench starts with a P

The beginning of the film deals with the love romance of a deep-sea diver and the daughter of an old curio collector, whose past life takes up a good part of the film and reveals to the spectator his younger days as he tells them the story of his romance and marriage.

An underwater exploration beneath kelp forests in the Pacific Ocean off the coast of Southern California. The film captures the birth of a shark, squids mating, a lobster molting, a fish protecting its nest from an octopus and a sea urchin, and the sea bed covered with brittle stars.

An astronaut on a deep-sea dive exploring a newly discovered trench soon finds himself confronted by a sinister & dangerous force.

A submarine adventure to the deepest depths of the ocean.

As the world's energy supplies dwindle, the Orpheus, a research submarine, delves into the deep of the Arctic Ocean searching for rare micro-organisms, but the crew soon find themselves in peril.

A group of divers set out on a journey to film and explore the beauty of the ocean. However, during their latest dive, their oxygen runs low, risking their lives as they encounter sharks and other marine wildlife.

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 below the ocean's surface where he confronts a mysterious force that has the power to change the world or destroy it.

Divers searching for sunken treasure witness the murder of drug dealers by modern-day pirates, but a killer great white is determined not to let any of them escape its waters.