Given its epically convoluted particulars, cagey metaphysics, and dialogue that's frequently (and most likely intentionally) indecipherable, Christopher Nolan's long-awaited action thriller Tenet boasts a narrative that I couldn't spoil even if I wanted to. And I kind of really want to, if only to explain why, after two-and-a-half hours, my brain was practically bleeding from the strain of trying to figure this thing out.