Decorated American submarine commander Eugene Fluckey, determined to go out with a bang, defies expectations and returns to USS Barb for one last patrol. On the eastern coast of Northern Japan, Fluckey and his crew push the boundaries of submarine warfare to new limits by launching rockets from their sub and landing a crew of saboteurs on Japanese land in order to destroy a coastal rail line. It's a highly aggressive and ambitious patrol that will forever change the way subs are used in battle.
