What should be a can't-miss concept (shark tribes warring for territorial rights and positions of power) somehow does, mostly due to tired dialogue and a forced aquatic vocabulary. Screenwriter and first-time novelist Altbacker quickly establishes and makes extensive use of underwater lore and lingo—Big Blue is the open ocean, green-greenie are kelp beds, chop-chop denotes the ocean's surface—that readers will find either fun or babyish, but that mostly feels intrusive (particularly in the inclusion of cardinal directions in random words: "lEast" for lost, "Southdenly" for suddenly). After Gray, a feisty shark pup, is banished from his peaceful, reef-dwelling clan, or "shiver," he and his friend Barkley venture into Big Blue and form Rogue Shiver with a quartet of sharks they meet. As Rogue Shiver becomes embroiled in a clash between two larger shivers, a web of scheming, shifting allegiances, and questionable identities emerges; a final showdown upends the balance of power and hints at Gray's future ascendancy. Readers looking for action and playground-style undersea banter ("You all suck algae!") will find both in abundance, and for some that will be enough. Ages 9–12. (June)