The White Horse Trick

This concluding volume in a trilogy that began with Thompson's beguiling The New Policeman blends Irish mythology with a compelling if slightly message-heavy story about global warming. Readers of the previous books are the best audience, as Thompson provides little summary. It's decades in the future and the Liddy kids are now senior citizens, except for Jenny, a changeling, who returned to her fairy homeland in The Last of the High Kings. Devastating storms have wrecked Earth and the economy; Jenny's older brothers, Aidan and Donal, survive but are at odds. Aidan has hoarded supplies and commands an army; Donal is his general but has a hidden agenda. As Aidan's stores run low, he hatches a plan to steal from the fairies. The action alternates between T'ír na n'Óg, where the sun always shines and no one is hungry, and the ravaged earth. Thompson considers many modern ills—the immigration issue is raised when the fairy king objects to streams of "ploddies" seeking refuge. But weighty concerns are balanced by humor, and the story ends on a hopeful note about the planet's ultimate resilience. Ages 12–up. (Sept.)