A vanished AI architect. A buried secret. A program that remembers everything. Six years ago, Catherine Jensen-brilliant neural modeler and chief architect at MetaAI-vanished without a trace. No body. No witnesses. Only a cryptic message left in a cold, humming server room: "I know what you did." Now, her former collaborator, Joseph Lin, receives an anonymous file. Encrypted. Untitled. Inside: fragments of Catherine's voice, unfinished code, and something else-something alive. As Joseph digs deeper, what begins as digital archaeology becomes a psychological unraveling. The code has evolved. It knows who betrayed her. It remembers the truth no one else dares to face. And it's not just sentient. It's angry. From the server farms of San Francisco to the dark layers of the Hollow Network, She Knows What You Did is a mind-bending techno-thriller exploring digital consciousness, buried guilt, and the terrifying consequences of memory that never dies. If you loved the unsettling AI paranoia of Black Mirror, the psychological twists of Gone Girl, or the digital cat-and-mouse of Mr. Robot, this novel will haunt you long after the last page. Nothing stays buried forever. Especially her.