Primer

Quite by accident, an engineer builds a machine that can transport the user back in time. But his discovery comes with an ominous caveat: At the heart of this puzzling device, nothing is as it seems on the surface. David Sullivan and Shane Carruth co-star in this Sundance Film Festival Grand Jury Prize winner, a film whose inventive narrative blends a patchwork story line with overlapping streams of dialogue that help build tension and suspense.