Few films beg repeat viewings like “Primer,” Shane Carruth’s 2004 time travel head-scratcher, which is impossible to fully unravel on first viewing, or on fifth viewing, or on fiftieth viewing. Not that those who’ve figured it out — like those who’ve designed elaborate, headache-inducing charts explaining all the time loops and who went where and when, etc., etc. — have really figured it out. If there’s a point to be gleaned from this micro-indie it’s in watching as something that started out as painfully complex spins even more out of control. If you didn’t get what its two amateur scientists (Carruth and David Sullivan) are doing in the early stretch, you really won’t get what happens when there are several of them scampering about, messing with time and who knows what else?
It’s so easy to get caught up in the not-too-penetrable plot that you can miss its indie bona fides. Carruth, a math major who designed software before hatching his own brainy movie, let no expense go to waste. As he pointed out on the commentary track to the film’s DVD (remember commentary tracks? On DVDs?), you can actually spot him occasionally mouthing the word “cut” at the end of shots — proof that nearly everything he shot wound up in the film. You don’t see that in his only other film, 2013’s similarly dense, similarly anxious “Upstream Color,” where shooting on digital made things easier. Oh, the burdonsome good old days.