I'll make this simple, if you read the previous two books in the trilogy and liked them, then read this. You won't be disappointed. 
 This contain spoiler for the previous books. 
 (view spoiler)[. 
 The world is a very different place due to the events from book 2. Humans now know of the alien's Quasing existence and their influence on human history. The Tan family is running an underground railroad to shuttle refuge aliens and their hosts that are being hunted by the United States government. Despite this Roen and Jill try to give their teenage son a 'normal' childhood. But when your a host to Tao, are being trained as a martial arts master and secret agent, being normal ain't easy. He also has learnt know how to talk to girls. 
 It references side effect of Roen now being separated from Tao but I wished it explored it more. (hide spoiler)] 
 The teenage boy hitting puberty with a girl moments are eye rolling but Tao's observations adds humour making it not so bad. 
 More points of views than the previous books but narrow focus, no globe trotting. Staying to the family brings more emotional stakes and has touching father-son moments. 
 It a satisfying ending to the trilogy while leaving the door wide open for it to turn into a series. Still page turning, action thriller with bond like villains with evil master plans and lairs.