The film describes a coup in the Soviet Union, where rebels took control of a nuclear missile base and threatened to attack the United States. The U.S. government urgently ordered the USS Alabama nuclear submarine to prepare for a counterattack, but at the critical moment of whether to issue an attack order, the submarine's communication system failed and it was impossible to determine the authenticity of the attack order. The submarine commander played by Hackman decided to launch the attack, but the new adjutant Washington believed that the matter was of great importance and that the message should be confirmed first, so he launched a mutiny and imprisoned his superior.