When four young free divers come upon a legendary shipwreck rumoured to contain millions in gold, they believe their dreams of buried treasure has come true. But nearby on the ocean floor they unearth another, more sinister mystery... The fortune hunting friends make a pact to keep quiet about both discoveries so they can excavate the shipwreck before a rival treasure hunter discovers their secret and beats them to the gold. But with so much at stake, their loyalties are tested. Facing hidden dangers at every turn, the hunters suddenly become the hunted.