Let me start by disqualifying myself to give an authoritative review of Boy Nobody by Allen Zadoff. I do not read thrillers as a general rule, and Boy Nobody is, if nothing else, a thrill
The narrator is a 16-year-old assassin trained by and (apparently) working for a super secret US Government agency. As a teenager he is able to ingratiate himself with his peers, become a friend of the family, and in short order murder the target with an undetectable poison. The death looks like a heart attack and who would suspect a kid?
By page 24 we have accompanied the narrator (whose real name we do not learn until very late in the book) into the secure Natick, MA, home of a Chinese businessman, watched him kill the man (the boy uses a special pen and the poison is painless), watched him slip away in the confusion following the man's "heart attack," and watched him disable four Chinese security thugs who suspect foul play. On page 25 we speeding down the Mass Pike in a stolen Mercedes with diplomatic plates.
The point of a thriller (in contrast to a mystery) is that the reader knows what bad thing is supposed to happen and is following the detective/the police to see if they can stop it, or, as in this case, following the narrator on his next assignment, which on the surface seems impossible. And in fact turns out to be more difficult than the narrator, or this reader, realized. For one thing, the narrator begins to recall events from his life before he entered The Program and they begin to complicate his assignment.
The book and the story zip right along. Many short chapters. One- and two-word sentence fragments. one line paragraphs. No extraneous description. Present tense. Lots of dialogue. Yet within the thriller conventions, Zadoff is able to give his 16-year-old some humanity, a code of ethics, and—more problematic—feelings.
If you can accept the idea that a super secret US Government agency is recruiting 12-year-olds and training them to be stone cold assassins, and the idea that the US Government is willing to use assassination as a policy, and that the super secret US Government agency has enough intelligence to know who should be killed, the Boy Nobody is a hoot. I don't accept any of those things, but I was still cheering for the narrator and shocked by the decisions he had to make.
It turns out that Boy Nobody is the first of a series (that Zadoff left the possibility open at the end of the book was clear). The title is now I Am the Weapon. The two more recent books are I Am the Mission, and I Am the Traitor. I'll mention them to my student.