In a world where memories can be bought, sold, and traded like commodities, 28-year-old Archivist Keira Salvo stumbles upon a memory fragment labeled "Echo 179." The fragment holds a cryptic and vivid scene of a murder, but there's no record of the victim or the killer in the vast city database. Keira becomes obsessed with uncovering the truth, only to discover that some memories are deliberately erased-for reasons far more sinister than she could imagine.