When is a stately home not a stately home? When it's a stately castle. At beautiful Belvoir Castle in Leicestershire, Phil is invited by the Duke and Duchess of Rutland to learn how the castle was built - and discovers a Regency love story to rival Jane Austen. The present-day Duchess Emma introduces Phil to her Regency predecessor Duchess Elizabeth, and allows Phil exclusive access to the Belvoir's usually off-limits archive. Phil learns that the castle's creators had to sell whole villages to fund the building work, and reveals the mind-boggling total cost in today's money. Phil encounters evidence of an aristocratic sex scandal painted on the ceiling, which was later disguised by royal decree. He searches for a lost railway under the castle, and tries his hand at modern-day pest control with a medieval twist.