Dean Corso (Johnny Depp) is highly skilled at his work – locating rare books for wealthy collectors – a position that requires dexterity, cultural expertise, nerves of steel … and few scruples. Corso is hired by eminent book-lover and scholar of demonology, Boris Balkan (Frank Langella), Corso’s mission: to compare Balkan’s newly acquired edition of the legendary manual of satanic invocation, The Nine Gates of the Kingdom of the Shadows, with the two remaining copies located in Europe, and ascertain the authenticity of the three books. From New York to Toledo, Portugal to Paris, Corso immerses himself in a labyrinth full of pitfalls and temptations, disturbing encounters, violence and mysterious deaths. Protected by an other-worldly creature (Emmanuelle Seigner) and guided by a force more powerful than himself, the hunter solves one by one the mysteries of the dreaded book and discovers the real purpose of his mission.