I think a small exposition at the beginning (think of the beginning of BL novels) set in a Starwars New Hope sort of thing could help. Just a paragraph to explain mankind's constant struggle against the alien, mutant, and heretic. How technology has slid into mystery and religion...that ought to be good enough.
Not a paragraph... Have you ever seen the Youtube series CinamaSins? "Oh boy, reading". No one goes to watch a movie to read, and I bet you haven't even read the essay at the beginning of Starwars. And if you have to read the paragraph to know what's going on it's going to fail.
Exposition should be done like the beginning of Transformers where you show and tell though images and narration.... "Assume this is real, here's the story."