A slow-burn thriller with a deep emotional core, an intricately plotted genre exercise, and an acting showcase for two talented young performers, Caddo Lake, on paper, sounds like the complete package. It takes a while to get going, and the first act is particularly testing, but it’s also the kind of film that gets better with every passing minute. In fact, Caddo Lake is at its best towards the end, when it ties all — or, at least two — of its narrative threads together, unleashing an emotional wallop that rivals only the sheer thrill of watching its well-executed twist.