The riveting and deeply immersive first installment in a new military sci-fi series—pitting amortal humans against a mystifying alien intelligence in a galaxy-spanning conflict—from New York Times bestselling author Ian Douglas.

Centuries in the future, the Galactic Authority reigns over millions of advanced civilizations throughout the cosmos. From deep within the Galactic Core, the Authority's principal Mind has won the allegiance of myriad nations, offering security, connection, and access to a network of interstellar Gates in exchange for compliance.

While technological advancement has brought interstellar travel and life-extending procedures to Earth, humans are struggling to maintain their sovereignty and cultural identity. The Galactic Authority's presence and technological prowess looms large, eliciting both awe and apprehension from a human society that finds itself at a crossroads: yield to the allure of advanced alien technologies, or preserve their autonomy in an increasingly fractious cosmic landscape.

Naval captain Alexandra Morrigan has little trust for the Authority, and by all accounts, war is brewing. When the extrasolar colony at Sirius goes silent, suspicions arise that Galactic forces or their proxies are pressuring humankind into submission. To preserve any hope of Earth's future, Morrigan and the forces she commands will do the unthinkable: travel through the Abyss gate, and make one last stand against the Galactic forces, whose powers may defy comprehension.