It depicts the life of Galileo Galilei and particularly his conflicts with the Catholic Church over his scientific theories.

While he questions the ideas of Ptolemy and Aristotle, the official scientific dogmas imposed by the Catholic Church, he remains secretive about his doubts.

His more candid friend, philosopher Giordano Bruno, is reported to the Inquisition for his revolutionary ideas and later executed as a heretic.

Still, Galileo continues his studies with a telescope constructed by Dutch technicians and perfected by him, and comes to the conclusion that Copernico's heliocentric system is valid.

Originally intended as a miniseries co-produced by Italian and Bulgarian film companies, radio and television company RAI refused to broadcast the finished film and sold the distribution rights to Cineriz, who trimmed the originally 105 minutes long film to 92 minutes running time.