From the front page of the PDF:
The Netherese sought to control the Oracle of Spellgard Keep, and nearly succeeded. She was only saved by binding her spirit inside a sentient golem. But for Lady Saharel to be useful to the Harpers, you must find a way to place her beyond the reach of her former masters. A Living Forgotten Realms adventure set in Luruar for characters of the Paragon tier (levels 11-20).
Note: This adventure is the third and final part of the Foresight trilogy, which began in NETH4-1 and NETH4-2. We recommend that you play the previous two adventures (in either order) before playing this adventure.