answer: In the first three books of the series, the Flock spends much of their time running from human- lupine hybrids (called Erasers) created by the School; Book 4 is mainly about the Flock rising against global warming ; Book 5 is about saving Dr. Martinez while battling environmental pollution ; Book 6 is about rescuing Fang; Book 7 is about stopping the Doomsday Group from destroying the world's population of non-mutated humans; and Book 8 is mostly about trying to stop the 99% plan.