When Russian rebels takes control of some ICBM's, the Americans mobilize. Among the vessels sent is the nuclear sub "Alabama". But before they leave they need a new X.O. and among the choices is Commander Hunter, who hasn't seen much action. But the ship's Captain Ramsey OK's him. While on the way, there is an incident and Hunter disagrees with how Ramsey handles it. They're given orders to attack but when they are in the process of receiving another order, the ship's communications are damaged, and the full message is not received. Ramsey decides to continue with their previous order while Hunter wants to reestablish contact first. The argument escalates and ends with Hunter relieving Ramsey. When some crewmen die later, some of the officers feel that Hunter is not up to the task so they team up to retake control. But Hunter has taken precautions.