The Fuller Memorandum (Laundry Files, Bk 3)

Computational demonologist Bob Howard, a T-shirt-wearing computer geek and field agent for the super-secret British government agency The Laundry, is catching up on his filing in the Laundry archives when a top secret dossier known as the Fuller Memorandum vanishes-along with his boss, who is suspected of stealing the file. And while dealing with Russian agents, ancient demons, and a maniacal death cult who have plans to raise a very unpleasant undead entity known as the Eater of Souls, Bob must find the missing memorandum before the world ends up disappearing next.