Ballad for a Dog (1969)

Remi is a man on the verge of old age who begins to have hallucinations. He believes he has found a dog, but the canine is just a product of his imagination. The man takes a turn for the worse when his only friend, his poet neighbor, moves. He is left alone with his hallucinations and tries in vain to separate fantasy from reality in this plodding, depressing feature.

Unfortunately the movie Ballad for a Dog is not yet available on HBO Max.