23rd century Earth exists in a fragile apartheid between humans and vantarians, the extraterrestrials who restored Earth after its apocalypse. Well-meaning but misinformed Alder Brites is aiming to finish their mandated service to the human military without incident when they meet the vantarian Sefynne Iyed, an alleged terrorist who raises questions Alder can't answer. Sefynne, reserved but passionate, is striving to correct the power imbalance on Earth when he discovers Alder has resources he needs. When the two realize they both seek an end to oppression, they form a reluctant partnership that evolves into much more. Together, they'll do things they'd never considered to make a difference. But with lives on the line, will the change they make be worth the cost?