The Accuser (film)

The Accuser aka LImprcateur is a 1977 French film directed by JeanLouis Bertucelli. After an executive is killed in a mysterious car accident, the French offices of his multinational company based in Paris is inundated with mysteriously threatening beribboned anticapitalist tracts, delivered overnight to everyones desks. When Americans from the head office get wind of these developments, they institute a search for the perpetrator which leads to mysterious subterranean passages under the companys skyscraper.

Source: Wikipedia