I thought the language and pacing of this were excellent. A family goes on vacation, taking the son's young friend, and soon learns that Jess does not have permission to be there, but he is being abused at home, so they also don't want to take him back. The protagonist, also an abuse survivor, is particularly fervent in this decision and the story ends up largely being an escape as the boys father tries again and again to track them down.
The thing that holds me from a full five on rating is that Colby Walker, as an abuse survivor, doesn't ring quite true. He is rash in his decisions about Jess, which is understandable, but if he is impacted this largely by his past, it seems there should be other signs of it in his life and person. Instead he has sold his successful business for millions, has an intact (if somewhat neglected because of his work) family. I just think to justify the poor decisions he needs a bit more evidence running through his life.
But that is probably the psychologist in me talking. Overall I found the story compelling and it really pulled me along.