“51 Nevada” (*1/2 out of four) was a tired and predictable alien-invasion thriller in which a young couple (Sam Schneider and Arielle Uppaluri) who witness a strange event involving possible otherworldly life form and then camp outside Area 51 hoping to find some answers but soon discover (yawn) a military coverup within the government who don’t want the truth to come out. Results are so by-the-numbers that it’s actually a surprise numbers don’t come out across the screen. “The X-Files” and “The Twilight Zone” used to cover stories like this in roughly 45 minutes.