Given how much teens enjoy stories of heroic adolescents, they will quickly become engrossed in the adventures of young Toby Tennant as he sets off to rescue his father and sister against the backdrop of a wintry dystopian Scotland beleaguered by ruthless thieves and super-intelligent, predatory black dogs. As Black Tide, Caroline Clough's second novel and sequel to Red Fever opens, a disease known as red fever has decimated the human population, and turned some wild canines into vicious packs of roaming cannibals. Moreover, some of the human survivors have banded together into vigilante groups to terrorize and capture people like the Tennants. When a gang of these ruffians takes his father and sister for use by a madman known as the General, Toby knows he must rescue his family while avoiding raiders and man-eating dogs.

Clough excels at drawing readers into her post-acolyptic vision, suspenseful plot, and likeable characters. Based on the author's vivid descriptions, one can sense the desolation of the ruined country as well as the pervading cold and hopelessness. Fortunately, though, the fast-paced yarn and relatable protagonist refuse to let readers get caught up in despair. This story will appeal to both girls and boys; Although Toby possesses skills and courage, he never seems superhuman and expresses a ralistic mixture of bravery and confusion. Toby is aided by a teenage girl named Tash, who can tame animals, cook just about anything, and wears a wolf pelt. Refreshingly, the interplay between the two quickly develops into friendship, without a hint of romance. While Toby performs more of the heroics, they both respect each other's abilities during their adventure. Toby's connection to his family is also admirable; he looks up to his father and wants to protect his little sister. Although readers see little of those characters in the story, they nonetheless remain vital because they exist constantly in Toby's anguished thoughts. Particularly gratifying is how much he frets over the safety of his much-younger sister, genuinely caring for her, even as he recognizes that her behavior can be obnoxious.

The antagonists of the story, the raiders as a group, the General and his followers, and the dangerous mongrels, seem oddly disconnected at times. Long periods of the book focus on Toby and Tash outwitting one foe, while the other group remains in the background. While readers learn that even the General and his men fear the wild dogs, Toby and Tash must stay ahead of both man and beast. To complicate matters, both dogs and wolves appear in the story, canines who, for an unexplained reason were never infected with the cannibalistic red fever. Ultimately, the self-styled dictator and his henchmen, bent on creating a new totalitarian state using slave labor, become much scarier than the supersmart packs of curs. And despite the disparate villains, the plot roars along, with every chapter ending in a cliff-hanger.

For those unfamiliar with Scotland, Clough helpfully provides a map of her home country at the beginning. Even so, readers not from the UK may have a bit of trouble with the slang and the use of locks to transport boats. Most of this information can be gleaned from context clues, however, as Black Tide sweeps its audience away on a whirlwind adventure.