Dostoevsky is Kurosawa's favourite author, and in Prince Myushikin, he admires the character's compassion and near godlike quality.

In The Idiot, Prince Myushikin becomes a Japanese returning from Okinawa to Hokkaido, where he innocently becomes involved in a menage a quatre. In a departure from Dostoevsky, both men become insane at the end of the film.

Otherwise, the film adheres to the novel; it is set in Hokkaido which is more similar to Russia than any other part of Japan; and Kurosawa refused to alter drastically the text. This places this film outside of a Japanese framework, and makes it one of the most difficult of Kurosawa's works.