The debut of Halfdan Ullmann Tøndel arrives with some unfair expectations — his grandparents are film legends — but finds a confidence and flair of its own.

If nonfiction films are determined to look, feel, and move like fiction, what’s the point of nonfiction filmmaking?

The film’s director, Walter Salles, narrates a sequence from his film, which is nominated for best picture. Its star, ...