Nate and his mother are running away, hiding out in a tumbledown* cottage in the middle of a forest. When Mum heads off for food and then doesn’t return, Nate is left alone and afraid, with the dark closing in all around him. But comfort can come from the most unexpected of places — an intriguing* girl on a mission to solve a decades-old treasure hunt, and the reappearance of an old friend from his past.

Lisa Thompson’s “The Goldfish Boy,” about a troubled 12-year-old with obsessive-compulsive disorder* investigating the disappearance of a toddler, was one of 2017’s bestselling children’s book debuts. Her follow-up, “The Light Jar,” is another mystery/thriller wrapped around psychological* themes.

Domestic abuse* is tricky territory for young readers and there is a terrifying passage in which Nate has a panic attack in an enclosed space, and readers come to understand his attachment to a jar filled with fairy lights that he keeps by his bed.

Plotting is Thompson’s forte* — she deftly* handles a thread in which Nate and Kitty solve clues from a decades-old treasure hunt. Less successful are Thompson’s dips into magical realism*. Passages in which imaginary friends turn up to help Nate navigate his troubles are presented as routine, with none of the transporting imagery of the best fantasy writing.

But this is a thoughtful and hugely empathetic* book: a consolation* for readers who, for whatever reason, might be feeling a little out of place in the world.(SD-Agencies)