El escalón 33

An old book purchased through the Internet hides astonishing mysteries”seven castles united by a secret bond and a hidden message that must be deciphered. Silvia, a book lover, works as a book conservator for the National Library in Madrid, but she is tired of her monotonous lifestyle and yearns for change. One night she discovers some mysterious texts that come with strange symbols whose meaning are unknown to her. What will these symbols reveal? Where will these mysteries lead the protago...