Stalin's Sickle(1987)

It is 1962. New Zealand is emerging from the austerity of the 1950s into a new age. Daniel is a nine-year-old Catholic boy, an only child given to colourful imaginings. He discovers that an old man who passes the plate in church bears a striking resemblance to the great Russian dictator, Joseph Stalin. Daniel starts to believe that the old man really is Stalin, come to take over New Zealand. Daniel takes it upon himself to give Stalin a fright and send him on his way. He hits on a method of doing so after finding where the old man lives and spying on him. Stalin is banished, but events take a strange twist, leaving Daniel with an even worse threat to deal with.

Official site