Star Wars changed cinema's economic model more than any other single film
On Agnès Varda's Cléo from 5 to 7 (1962) and what it does with time that almost no other film does.
Varda's film follows a singer during the two hours she waits for the results of a medical test. The film runs in near-real-time: the film's duration and the story's duration are almost identical. This formal choice, which Varda was explicit about, is not a gimmick. It's the point.
Being in Cléo's time — not watching it from outside but inhabiting it alongside her — changes what it means when she looks at her reflection. It changes what it means when she walks through Paris. It changes what it means when she has a conversation. Because we are in her time, we are also in her uncertainty, and uncertainty about whether you are going to live feels different when it's present-tense rather than retrospective.
Varda made the film when she was 33. She was not ill. But she understood something about what it means to be alive in a body that might fail that she committed to celluloid with complete clarity.
Cléo from 5 to 7 is the film I recommend most often to people who think they don't like French New Wave. It is the most immediately accessible great film of the movement.