At night, a passenger train derails and plunges into a deep lake. A few survivors find themselves trapped among the sunken wreckage. The heroes attempt to find a way to the surface and escape their watery prison. Soon, the passengers realize they are not alone in the depths. A mysterious and deadly predator begins hunting the survivors. The people must face primal fear and enter a brutal struggle for survival. The film is presented in enhanced UHD quality using HDR technology.