A new technologically-superior Soviet nuclear sub, the Red October, is heading for the U.S. coast under the command of Captain Marko Ramius. The American government thinks Ramius is planning to attack. A lone CIA analyst has a different idea: he thinks Ramius is planning to defect, but he has only a few hours to find him and prove it - because the entire Russian naval and air commands are trying to find him, too. The hunt is on!
New York, 1961. Alexander Ivanov, a high-ranked Soviet bureaucrat, reluctantly defects to the West while is part of a diplomatic mission, feeling the grief of being unable to know the fate of his wife Katya, whom he has had to leave behind in Moscow. Only many years later, in 1991, he will finally find out the truth when his niece Lauren travels to Moscow to participate in a painting exhibition.
Colonel Stok, a Soviet intelligence officer responsible for security at the Berlin Wall, appears to want to defect but the evidence is contradictory. Stok wants the British to handle his defection and asks for one of their agents, Harry Palmer, to smuggle him out of East Germany.