As I mentioned in a recent review, the primary issue that befalls the majority of short narrative work is a tendency to cram too much plot into a limited amount of time. It behooves filmmakers working in the short form to stick to a single concept or theme and fully commit to depicting it, rather than overextending themselves with multiple themes. (Interestingly enough, this problem rarely arises in short animation, most likely because animation directors don't feel the need to tell stories in the same way live-action directors do.)
This Belgian fantasy is highly conceptual—it tells the story of a soldier who died during WWI and was subsequently sent to a sort of steampunk limbo, in which he's tasked by a mysterious old man with photographing the shadows of people as they die—yet director Tom Van Avermaet is able to keep everything in check. He achieves this by eschewing unnecessary exposition and focusing on more expressive elements such as production design, which emphasizes period detail as well as science fiction iconography. The dreamlike nature of the setting allows Van Avermaet certain liberties with narrative logic, which he gamely uses to his advantage.
The old adage of "show not tell" proves double here. Rather than waste time explaining the logic of his film, Van Avermaet allows a healthy dose of mystery and ambiguity to hover over the action. As the film progresses, the details of the story emerge organically from the characterizations. The composure Van Avermaet displays is not only befitting from a filmic standpoint, it's also damn refreshing. By assuming his audience is both smart enough and patient enough to allow the film to unfold on its own terms, he's able to pull off a denouement that's as surprising, moving, and effective as I've ever seen in a short narrative film.