Horror with a Twist - And a Drop

Rating: 7/10 (16 March 2017)

A girl in a car accident awakens to find she's in an underground bunker with an oddball farmer and an average Joe with a broken arm. The farmer insists some outside calamity* (nuclear war, aliens?) has occurred, so he's keeping her safe with him. Until when, no one knows.
The next part is a taut, claustrophobic thriller as the two "guests" try to figure out if Howard is making it all up or is just crazy.** They find some clues about his daughter and the outside world, where a ravaged woman shows up at their door to die.
Their plans for an escape go awry, revealing that Howard is indeed crazy. She escapes, killing Howard, to find the air isn't poisoned.
As another commenter noted, this would be a good ending point. But then the twist: there was an alien invasion **So it was both! And they come after the girl. Suddenly this rather normal person turns into MacGyver, downing an alien/ship with a homemade Molotov. (Note: Scotch doesn't quite cut it here. And where'd the beast on the ground go?) She then learns about the resistance on the radio and turns to join them.
*Major nit: After whatever calamity Howard says may have occurred, wouldn't you want more info? Howard's bunker doesn't have so much as a radio. Okay, maybe he has reasons to keep things secret - even if he's right about aliens (because he is crazy and wants a 'family') with him. But the other two never ask a single question about this. "What is the radio saying? TV? Cable? Landline? Cell? Internet?" Maybe some are down, but to never ask about any??