A fast-paced, page-turning literary thriller that is half The Rule of Four and half The Matrix, from the author of the New York Times bestseller The Magicians.


A long lost library. A priceless manuscript. A deadly secret...

About to depart on his first vacation in years, Edward Wozny, a young hot-shot banker, is sent to help one of his firm's most important and mysterious clients. When asked to unpack and organise a personal library of rare books, Edward's indignation turns to intrigue as he realises that among the volumes there may be hidden a unique medieval codex, a treasure kept sealed away for many years and for many reasons.

Edward's intrigue becomes an obsession that only deepens as friends draw him into a peculiar and addictive computer game, as mystifying parallels between the game's virtual reality and the legend of the codex emerge and the lines between reality, fantasy and mysterious legend start to blur ...