This book is great the only thing I can grump about is the fact that he's accomplished so much at 4 years of age and the fact that Feldman doesn't think it's strange that an 4 acts like a mature adult.
Not sure what kind of catalyst but a type of super zombie with the ability to blend in with regular humans kind of like hiding in plain sight It has small quirks if one was smart enough to notice like mark to realize it was not what it seemed