He acquired the property of Moldavie Residence under the false pretense that a deceased mage's widow wished to sell the estate, only to find the manor is apparently haunted. After asking the witcher which School he belongs to, he will discuss the Contract: Doors Slamming Shut.
During his investigation of the manor Geralt determines that a powerful earth elemental, Therazane, is imprisoned in the basement of the mansion. The monster trying to get out from behind the magical barrier was shaking the whole house.
Geralt defeats the monster and returns to Dysart to inform him of the results and the existence of the cavern beneath the manor--Dysart appearing eager to explore said caverns. If the wooden supports are destroyed during the fight with Therazane, then Dysart will be killed after he later goes into the basement. Geralt can come back to find his servant near the gate who informs him of the incident.