The book was banned by the occupying Soviet regime. When offered the film adaptation, Miloš Forman refused, fearing for his sons in Czechoslovakia. Instead, he phoned a friend in San Francisco.

THE UNBEARABLE LIGHTNESS OF BEING (1988) is Philip Kaufman's three-hour adaptation of Milan Kundera's "unfilmable" novel, with Daniel Day-Lewis, Juliette Binoche, and Lena Olin. Sven Nykvist shot it. Walter Murch cut it.

For the 1968 Prague invasion sequence Kaufman hired a Czech consultant named Jan Němec. He used footage Němec had shot himself, on the morning the tanks arrived, before smuggling it out to Vienna. Němec makes a cameo as a man capturing the events on camera.

Milan Kundera wrote of the finished film that it had very little to do with the spirit of the novel or its characters. Miloš Forman, who won Oscars for directing Amadeus and Cuckoo's Nest, had studied under Kundera in Prague. One wonders what the teacher might have thought of a version by his old student.

Kundera never allowed anyone to adapt his work again.