A tragedy set in the world of diplomacy, with Zbigniew Zapasiewicz cast as an intellectualist disappointed with the freedom he has fought for. The title persona non grata is Wiktor, a former anti-communist activist, now the Polish ambassador in Uruguay. In the past he was an idealist, now he is lost in a world where there is hardly anyone one can trust. His obsessive suspicions of dishonesty or even treason concern not only his work, but his personal life, too, not only the present time, but past as well. And the history goes on, the political regime was successfully changed, Wiktor's beloved wife is dead, the past becomes blurred and equivocal.
An important issue in the film is death - this time not of the character himself, but someone else's death. How to cope with the sudden loss of your loved one? Persona non grata is a story about how difficult it is to accept the loss of the loved one, about quest for internal harmony despite dissonances from the outside.
Wiktor's personal drama is intertwined with a sensational plot with spies, smugglers and exotic scenery (some scenes were shot in Uruguay).