Consider the Bourbon biscuit. It comprises of two dark chocolate biscuits sandwiching a chocolate fondant. It is a straight forward recipe made from standard elements. Yet multiple companies manufacture the Bourbon biscuit and they're all slightly different in texture and taste due to minor variations in the base ingredients. You can make the same point about baked beans. Dark Skies is the cinematic equivalent of these products. It is competently made, offers what you know and expect in a slightly different fashion. That doesn't sound such a bad thing, does it? Well let me put it another way. It's generic and predictable.