Five hundred feet beneath the ocean's surface, the crew of the Ohio-class ballistic missile submarine "USS Colorado" - the most powerful nuclear submarine ever built -- receive their orders. Over a communications channel designed only to be used if the U.S. homeland has been wiped out, they're told to fire nuclear weapons at a foreign country. Captain Marcus Chaplin demands confirmation of the orders, only to be unceremoniously relieved of duty. XO Sam Kendal finds himself suddenly in charge of the submarine and facing the same difficult decision. When he also demands confirmation of the orders, the Colorado is fired upon and hit. The submarine and its crew, honorable patriots, now find themselves crippled on the ocean floor and declared rogue enemies of their own country.