Blow Out begins with a broadly visual joke, nearly four minutes long, about filmmaking. It ends with a second joke on the same subject, this one more complex, pointed, and black as tar. Over the course of the narrative, the material has turned rancid, so discoloured and malodorous that it’s hardly funny. That’s because, between the two grand gestures that bookend the film, writer-director Brian De Palma has traced a hero’s journey from idealism and optimism to disillusionment and despair. If cynicism were a superhero franchise, Blow Out would be its origin story.