As the last descendants of Earth struggle to survive in an aging undersea colony, a troubled young cargo-sub captain joins forces with an untested crew to destroy a weapon that threatens the human race.

SYNOPSIS:

Long after our modern world has fallen, the human race lives deep under the ocean in massive domed cities. In one of these cities, young, inexperienced, and broke, Jake Stone is approached in the middle of the night by a group of people who want to rent a cargo submarine he inherited to transport medical supplies. Desperate for money, but also haunted by the memory of killing his girlfriend a year earlier to save the ship he now owns, Jake reluctantly agrees. Led by an attractive Shipper’s Guild officer, AJ Juno, and a former governmental official, Nia Moon, Jake watches as an eight-member crew enters his ship and prepares it for departure. As they leave, Jake feels suddenly sleepy and goes to his quarters for a nap. When he wakes up 18 hours later, he discovers that his ship has veered off its original course. Realizing that his long sleep must have been drug-induced, but also knowing that he is outnumbered eight to one, Jake decides to play dumb until the odds are more in his favor.

On the outer border of their colony, they enter a domed structure containing an overgrown forest and Jake learns that the crew has come to search for a valuable relic from Earth’s long-forgotten past. As soon as they locate the object, a spike-covered sphere, a large mutant cat attacks them, nearly killing one of the crew. Before the monster can strike again, a naked woman leaps from the forest and kills it with her bare hands. After a mad dash back to the ship with the object and the strange woman, they plunge back into the sea. When the others retire for the evening, Jake finds the woman, now called, Jane Doe, standing next to the recovered object. She touches the sphere's surface and it opens to reveal a small cockpit inside. Jake crawls inside to check it out and she follows him, repeating, “Save you.” The opening suddenly closes, trapping them both inside. A screen inside comes to life showing two of the crew with guns drawn, taking the rest of the crew captive. Frustrated that he can’t help, Jake yells at the screen, “Just shoot each other!” The men suddenly turn and fire their guns, killing each other in cold blood.

As Jake rejoins the crew, they receive a communication from the colony’s border guards threatening to board. Nia says that the object is a mind-control weapon they must keep from the guards, so Jake comes up with a plan to dispose of it in a deep ocean trench. Jake and Nia run to the cargo bay and open the lower hatch to push out the object. They are successful, but Nia’s suit gets caught on one of the object’s spikes, and she’s pulled down with it into the dark, cold ocean. Her final words are a plea to Jake to protect her crew. Afterward, Jane Doe shows Jake what she learned about him from their time inside the sphere: instead of killing his girlfriend to save her crew, she killed herself to save him. Relieved of the guilt he had been carrying for so long, but also acknowledging the sacrifices others have made for him, Jake finally accepts the responsibility of being captain. The crew agrees to stay and try to make a life for themselves on his ship, but as they depart, Jane Doe looks at him knowingly and wonders if he understands the dangers that lie ahead.