NOMAD

Gabriel Sandro Fuentes, 11-year-old ambassador of Earth, fends off an alien invasion.

The superb conclusion to this two-part tale of space diplomacy restarts Gabriel's tale at the very moment Ambassador (2014) concluded: when he meets the shockingly human child ambassador of the nomadic, spacefaring Kaen. The Kaen are still out for Gabe's blood, Earth is threatened by the species-destroying Outlast, and (no less world-shaking) Gabriel's father's been deported from the United States to Mexico. Gabriel convinces the Kaen ambassador that he's her best ally against the Outlast, so he joins her on Kaen territory. The Kaen's jaguar-shaped shuttlecraft, Olmec-style spacesuits, and terrible tamales perturb Gabriel, though his fear that aliens may have been responsible for Mayan civilization prove unfounded. In the fascinatingly familiar craft, Gabriel and Kaen join with Ambassador Nadia, the previous child ambassador of Earth, who flew into a time dilation when she tried to fight the Outlast—in 1974. Soviet Nadia and modern American Gabe get on swimmingly, despite the culture clash; after all, they're both diplomats. Nadia has a vision disability, which Alexander handles with welcome nuance. Though Gabriel's not all that believable as an 11-year-old, he's thoroughly credible as an empathetic hero. With Nadia and Kaen, he relies on one hope to stop the Outlast: "Communication is possible. Communication is always possible." Maybe that's true on Earth, as well.

Alexander is clearly passionate about science, space exploration, and social justice, but he never allows that passion to shortchange the crackerjack adventure