This movie refuses to pretend to be anything other than precisely what it is: a camera that stares. In practice that means it risks being mistaken for a beautifully photographed but stuffy exhibit of period costumes and decors.
It’s not. It’s a camera staring with limitless curiosity at the face of Jean-Pierre Léaud.
A good example of this is an extremely long-take from early in the film. The movie sets its gaze upon a moment of Léaud’s performance, shooting him in profile in extreme close-up as he holds a smile for the members of his court attempting to entertain him in his bedroom. At first the smile is natural and pleasant. But then subtly the joy drops out of it, and it becomes a mask for fatigue. Nothing—and yet everything—has changed. And then a tiny muscle lying under the loose skin of Léaud’s cheek begins to twitch, intermittently at first but then insistantly. The smile never drops, the eyes continue to shine, but by the time the courtiers leave, the cost of the performance—the king’s and the actor’s—has registered.
More generally though, the film stares at a face made famous when it was young. The face has aged, but the movie and those of us watching it remember that it once looked like this:
The movie stares at this face, studying how it has changed with age, and searches for what of the youth remains.
The beauty of the film is that as it stares at the aged face, it discovers (and shows) that all of that remembered beauty is still there. Changed but there. And still compelling.