During the height of a Cold War, a drunken reporter from Sweden disappears without a trace while on a business trip in Budapest.
Meanwhile, the tabloid for which he was writing sounds an alarm, with the Swedish government trying to avoid direct confrontation with the Hungarian police.
Martin Beck, a detective, takes the case, and is sent behind enemy lines as a private citizen, to find the reporter and bring him back to Sweden.
However, the official of the homicide commission faces a dilemma: How will he be able to locate a Swedish national in a city of two million?
They need to interrogate charming Ari, a Hungarian girlfriend of the missing person, to gather the clues on his whereabouts.