The Swissmakers(1978)

Original title: Die Schweizermacher

This romantic drama follows two policemen whose job is to investigate the lives of foreigners who have applied for Swiss citizenship. Among the applicants they must screen are a French psychiatrist and his wife, and a ballet dancer. The married couple are quickly accepted, but the dancer's life offers some objections. However, since the younger policeman has fallen in love with her, there is a chance that she, too, will win Swiss citizenship.