From the first page of the PDF:
The Second Battle of Elturel ended in a single terrible instant. The divine relic known as Amaunator’s Companion exploded, taking most of Najara’s invading forces with it and leveling most of Elturel. Now that the smoke has cleared,
the heirs of Elturgard are organizing an expedition to learn what remains of the city, if anything. They also hope to retrieve some items they were forced to leave behind. They need powerful protectors, for who knows what they might find amidst the ashes of Elturel. A Living Forgotten Realms adventure set in Elturgard for characters of the Paragon tier (levels 11–20). This adventure is a loose sequel to the Elturgard Story Area adventures and takes place after the events of ADCP5-1 Home’s Last Light. The adventure includes a retirement option for higher-level characters.
Although this is a one-round adventure, playtest experience has shown that it can run long. You may want to allow 6 hours of play time if possible.