![Harrison Ford](http://image.tmdb.org/t/p/w92/7CcoVFTogQgex2kJkXKMe8qHZrC.jpg)
Surveillance expert Harry Caul is hired by a mysterious client's brusque aide to tail a young couple. Tracking the pair through San Francisco's Union Square, Caul and his associate Stan manage to record a cryptic conversation between them. Tormented by memories of a previous case that ended badly, Caul becomes obsessed with the resulting tape, trying to determine if the couple are in danger.