Reading the publisher's blurb gives you an idea of the plot but reading the book is something different. Boy A is "reborn" following a spell in various prison establishments and is let free. This is his story - but as we go through the chapters of the novel, each one starting with a letter of the alphabet, his backstory is revealed - it seems that Boy A can never escape his past, despite having done the time for his crime.
The reader is made to feel something of a voyeur - because the shame of Boy A (now called Jack) is so deep. There are indications that Boy A is in the same position as one of the killers of Jamie Bulger - of being described by the media as a monster who has done something unforgiveable and inhuman. The reader is put in the position, frequently, of the public. There are allusions to the publicity surrounding the crime in the tabloids, and the role of the media in Jack's life is fundamental to the plot: despite the theory of crime and punishment, it seems that there can be no redemption, and no new rebirth.
The author intends us to feel not only pity for the protagonist, but also to explain how he has come to be this way - exploring through the medium of the old case files and the history of Boy A how he has never received the love and attention that would have led him to grow up as a socially responsible member of society, and thus how Boy A has lacked the appropriate stimuli to develop properly. There is even the possibility that Boy A was the accomplice to the crime committed by the other boy, and that he was unaware of the extent of the crime caused. As a child he has been tried in an adult court, and both prior and post sentence, he has never really been cared for by adults. Only his cell mate and his probation officer have a link with him.
Above all, this is a story about love and the lack of it, and of innocence and corruption - Jack's probation officer has formed more of a close relationship with Jack than with his own son, from whom he is estranged following his divorce from his wife. The denouement centres around jealousy and envy - Zed being the complete opposite of Boy A, yet someone who lives within the law as it is understood by the media.
If I were to summarize the obvious about this book it would be "hug a hoodie". But this misses out the way that the book plays to the reader - rather carefully manipulating the reader throughout, so we are put through a mixture of responses (voyeurism, shock, horror, sympathy, empathy, distaste and judgement) as we work through the alphabet of who Jack is: Jack the lad, Jack of all trades, all work and no play makes Jack a dull boy - and who he might, with a bit of luck, become.
This is an excellent novel, and worth spending time on, if only to explore your own reactions to the situations described.