Alex Holbeck (Martin Sheen) is recruited as a CIA agent. He is sent to East Berlin on a mission to steal an Enigma code scrambler. This is part of an attempt to stop the Russian assassination of five Soviet Union dissidents which is planned for Christmas Day. What Alex doesn't know is that the CIA already has a code scrambler. By stealing the scrambler in Berlin, they are trying to convince the Russians that they don't have it.