Warriors #3: Forest of Secrets

Book three of the Warriors series drops readers back into the world of Clans of wild cats living in the forest, where the balance of power is fragile enough that former allies can turn on each other without warning. At the center of it, a cat named Fireheart won't let go of the mysterious death of Redtail, a respected warrior from his own Clan, and his digging starts turning up secrets that plenty of cats in power would rather stay buried. Erin Hunter's book runs 340 pages, aimed at ages 6 to 10, and the forest itself does real work as a setting — a shadowy place where every sound could mean an ally or a threat.

Hunter doesn't hand readers an easy villain here, which is what separates the book from simpler animal-adventure stories: loyalty and truth-telling work against each other, since finding out what really happened to Redtail threatens to destabilize the very Clan Fireheart is loyal to. That moral complexity is a step up from most talking-animal fiction, rewarding a reader who's outgrown simpler animal stories and wants more intrigue in exchange for tracking a large cast of characters. The stakes are real enough that the ending carries weight rather than wrapping up too neatly, which is exactly what keeps this series' fans reading past book three.