Shane Carruth's latest film Upstream Color is one of the most beautiful, compelling, and difficult-to-understand films I've ever seen. It took me three times viewing it to even have a clue of how to review it. Unlike Primer, which operates at the will of the relatively well-known mechanism of backward time travel, Upstream Color is pervaded by far more mysterious and unfamiliar phenomena. ~ While the visuals would be stunning by themselves, the sonic accompaniment elevates the arresting quality of the film enormously. The soundtrack is absolutely gorgeous and is a masterpiece all its own. If I could take my eyes off of the screen for one second I would close them and drown in the music. Even so, the sound of this film is much more than mere music. The sounds of all manner of objects [natural as well as man-made] play a vital role in shaping the film's atmosphere. I don't believe I have ever before beheld the setting of a film giving rise to its own soundtrack right before my eyes! Upstream Color is undoubtedly a work of art, and should be approached that way: pay close attention, but do not expect the underlying significance of everything to be obvious because you have been attentive. The first time you watch it you may not understand it at all. There is nothing wrong with that. What this film offers is an experience that transcends understanding.