The Cipher is addictive. The first-person narration manages to name a lot of details, to make room for a lot of backstory, while still sounding like it could be the transcript of someone telling you a really long anecdote.

The "horror" of the entire novel is, perhaps, contained in how fast the unbelievable becomes mundane. In how easy it is to accept the premise of the book and perhaps wonder what we might do, faced with similar circumstances.