LOL Andromeda strain, is more realisic than an alien invasion, there is absolutely nothing here on earth worth crossing millions of light years to fight for then gather, anything we have can be found in space in much vaster quantities..well except us but who the hell would want something so cranky, demanding and nasty as a human being.
The one that always cracks me up with Hollywood invasion plots is that the aliens are here for our water. I mean water? It is very commonly found in outer space including the outer reaches of the solar system and you don't need to drop down into a gravity well to get it. There was one movie recently where a scientist character mentioned that they wanted our water because it is liquid and the stuff in space is frozen. So apparently the aliens are smart enough for interstellar travel but can't heat ice.....
Aliens coming to earth for biological material (as in E.T.) makes a lot more sense.
So it's a Rook? Makes sense.
I am sure the Rooks will make sure all the hours HT is putting into star mapping for AH3 is not wasted.