Un sourire... is just a guy reciting the script of Hitchcock's The Birds while we can hear the other movie. He walks with a companion through a forest and the night slowly comes.
Strangely, this is a very captivating movie. The forest slowly turns weirder and weirder, with the author coming up with beautiful ways of showing it.
Now, captivating doesn't mean it can't be boring. Is almost two hours of reading and walking. I for one enjoyed this way more than I would have expected, but please consider it well in case this is shown in some festival near you. Don't come here complaining about nothing happening in this film.