The City of EmberThe City of Ember by Jeanne DuPrau
I read this a while ago after catching the last of half or so of the film, City of Ember adapted from it. I found what I saw so-so, despite a good performance from a young Saoirse Ronan as Lina, and from others in the cast. But the story was intriguing, so I sought out the book. It is not unusual in setting or form, being an adventure in a post-apocalypse world, but I think it is very well done. The main character is Lina (age about 12?) who becomes a messenger in the city, which we learn is a last refuge in the dark, with only the machines of the long-gone builders to provide lights and other needs for life. But the power cuts are becoming more frequent, longer and much more frightening. Lina's little sister finds a box in their grandma's house (their parents are gone), and manages to chew most of a piece of paper it contains that has some sort of message or instructions.
The story is a well-paced adventure, with a bit of puzzling from the half-chewed message, the mystery of the city and what has happened to the world, and character development as Lina learns what to do. She must be responsible beyond her years, and discovers that some adults are dangerous. Her care for her sister and her grandma is quietly affecting, and what happens with her grandma is quite moving. Although this story is aimed at young adults I suppose, I found it engaging and enjoyable. There are three more books in the series, one a prequel. From what I have read of readers' reviews, I hope to read the sequels later, but will probably give the prequel a miss.