Instruct: Classify Amazon reviews into positive or negative sentiment
Query: unsatisfying

I didn't find it confusing, and I didn't find it too cerebral and I didn't find it over my head; I found it unbelievably tedious. A movie about time travel where almost nothing happens. Granted, having read SF for more than thirty years, I suppose I'm a bit jaded. There's nothing, after all, about the subject that Robert A. Heinlein didn't already do to perfection sixty years ago. 95% of the film consists of a couple of yuppies talking, yay. And they're not even particularly likeable yuppies. The acting is unimpressive at best. No offense intended to those who liked the movie or to the writer/director/ producer/actor Shane Carruth; I liked the idea of the movie, and what was accomplished on $7,000 budget was impressive, but I didn't find the movie enjoyable---and barely watchable after a point.