This story covers a short, but impactful (I know that's not a recognised word, but it should be!)
period of a young boy's life.
In the opening, Danny and his Dad are sitting at home, fretting over the unusually late home-coming of Danny's Mum. Eventually, she turns up, flanked by two police officers. She has collided with Andy, who is slightly younger than Danny, as she was driving home. Andy is in a coma in hospital, and his chances of pulling through are slim. Mum is drowning in her guilt and has become uncommunicative.
Tensions rise. Other characters are introduced, including Andy's sister, Sarah, who becomes central to the plot. The interactions between all of the players make the story roll along at a brisk pace. The events are not predictable, which makes for interesting reading.
As a quick read, it is possible to get through the whole book in a single sitting, and setting time aside to do that would be worthwhile. Once you are into it, you will want to continue until you reach the conclusion.
I did like this book, although not quite as much as the only other John Boyne that I have read, The Boy in the Striped Pajamas.