Story of an ex-Navy Seal who is now a combat medical officer assigned to a state of the art Russian sub with a nurse. This is to answer a call for help set off by a dying member of the original crew. The sub has been overtaken by terrorists who are bent on destruction. So we see the duo try and gain control back. And this happens with the fear of the US Naval Forces is about to unleashing everything it has got on the terrorist sub to prevent it from launching its arsenal. Be careful of the early explicit sexual scene in the first quarter of the movie. A couple of unexplained scenes towards the end. Watch it when you have the time. Nothing to miss out even if you let the show run while you go get yourself a cup of coffee: slow moving.