La forêt noire (1968)

Inspired by the life of 19th century composer Robert Schumann, this fiction tells the decline of Hans Richter, a great German musician. Then dying, he feels his reason leaving him, while his wife gets closer to his disciple, Friedrich Turner, who has endless admiration for him. After his death, Turner helped make him a legend.

Unfortunately the movie La forêt noire is not yet available on HBO Max.