Sisters Lisa (Mandy Moore, "This is Us") and Kate (Claire Holt, "The Originals") become trapped at the bottom of the ocean when a diving expedition to observe sharks goes horribly wrong. When the cable attaching the cage sinks to the bottom of the ocean, the sisters must figure out a way to get back to safety battling injuries, lack of oxygen, and worst of all, bloodthirsty, great white sharks.
