The Ninth Gate (1999)

A rare book dealer, Dean Corso, is hired by a wealthy collector to validate a copy of a demon text. As he travels to assess the other known copies, he is pursued by the wife of the previous owner, encounters mysterious engravings and murders, and discovers that the secret to the Nine Gates can be found in a combination of all three copies. In the end, he is able to travel through the ninth portal with the help of a mysterious girl.