When genetic scientist Macallan Orsel discovers an ancient secret hidden beneath the Pacific Ocean—a city called Leviathan inhabited by immortal humans—her carefully constructed life in New York City is suddenly thrown into turmoil. Drawn into a clandestine struggle she never knew existed, Macallan is thrust into the middle of a dangerous conflict between Leviathan’s immortal residents and the ruthless Blackdoor Group, a covert government agency determined to exploit the immortals’ powerful technology for its own ends.

As Macallan delves deeper into the mysteries of Leviathan, she uncovers shocking truths about her own heritage and the longhidden history connecting her family to this hidden world. Her journey propels her across continents—from the bustling streets of New York and secret laboratories in Japan to hidden enclaves in India and the remote peaks of the Himalayas.

Caught in a web of espionage, betrayal, and shifting alliances, Macallan soon learns that trust is as perilous as treachery, and that the stakes are nothing less than humanity’s future.