Ridley Scott's 2012 "Alien" prequel "Prometheus" has been criticized for its vague lore and screenplay that wraps mysteries inside enigmas. I'm a fan of the picture — and Scott's 2017 sequel "Alien: Covenant" — but I will concede I remain frustrated that the movies didn't dig deeper into the alien Engineers. These ancient and inscrutable beings created us in their image, "Prometheus" reveals with its opening scene, yet now they want to destroy us. The movie doesn't answer why. Did the Engineers always intend humans as Xenomorph breeding stock? Did our ancestors fail their parents (perhaps by killing one of their emissaries)?

"Prometheus" ends with Dr. Elizabeth Shaw (Noomi Rapace) and android David (Michael Fassbender) flying off to the Engineers' homeworld, intent on getting answers. "Covenant" doesn't give them, for David wiped out the Engineers with their own bio-weapons and then killed Shaw. Just like the main characters of "Prometheus," I keep wrestling...