Earth is uninhabitable. Tau is our home now. With that terrifying message, Jo and her family learned the truth: They are trapped forever on Tau Ceti e. But the planet's current occupants--the Sorrow--are not interested in sharing. The fragile peace Jo negotiated abruptly shatters, and soon a bloody battle is raging between the Sorrow and the Pioneers. As tensions rise, the survival of everyone Jo cares for seems less likely by the second. When a betrayal that shocks Jo to her core threatens to wipe out both Sorrow and human life, Jo must find the strength to speak up once more--and bridge the gaps between all the warring factions--or lose forever the only home left to her.