I spent the last 20 minutes of William Eubank's intimate sci-fi thriller The Signal with my jaw hanging open. The movie's a slow burn that keeps its characters in the dark about what the hell is happening to them. Eubank's greatest feat is that he keeps the audience in the dark, too (or at least, this member of the audience). And then, when there is light, the movie explodes like a fireworks display. It's bright, exciting, and from moment to moment, unpredictable.