"a premise that keeps you awake at night..." Ok, assuming you know something about Christianity, and aren't easily offended: How about the book of Revelations, and the second coming of Christ - suppose God and the angels are an advanced human species returning to bring their experiment (us) home, and having to fight their own civil war with those who want the Earth for themselves (Satan and his legions...) in the process. This is an idea in a story I'm nearly finished with entitled "The Ark" - and it gets into a lot of stuff with biblical references too - i.e., it will only carry 144,000 passengers (Jehovah's Witnesses say that's the number of people that are going to heaven...) back to God's Realm. (Heaven, if you will) I'm not ready to make that as a movie yet, but I'd love to sell the screenplay to someone else.