Book Review: Invasion: Earth by Harry Harrison An alien ship crashes to Earth and when investigated turns out some violent aliens and their captive from another race. Having befriended the captive, there is a chance to gain a powerful ally in a war which is rolling towards Earth. This is typical of the sort of science fiction book I used to love when I was younger. Short, to the point, it has a good idea and investigates it through to the end, which may or may not have a good twist at the end. Harry Harrison is particularly good at writing this sort of book, but the 70's and early 80's has loads of examples of them from all sorts of authors, including luminaries like Isaac Asimov and Arthur C Clarke. The characters are relatively smart, the good ideas spread around a few of them so it doesn't seem too unrealistic, and you can see the logic behind their arguments. All in all it's just a nice little SF book which will give you some entertainment for a few hours.