After the Cold War, a breakaway Russian republic with nuclear warheads becomes a possible worldwide threat. U.S. submarine Capt. Frank Ramsey signs on a relatively green but highly recommended Lt. Cmdr. Ron Hunter to the USS Alabama, which may be the only ship able to stop a possible Armageddon. When Ramsay insists that the Alabama must act aggressively, Hunter, fearing they will start rather than stop a disaster, leads a potential mutiny to stop him. On a U.S. nuclear missile sub, a young First Officer stages a mutiny to prevent his trigger happy Captain from launching his missiles before confirming his orders to do so.