Phil explores the magnificent Blenheim Palace in Oxfordshire and gets to know its formidable builders, John Churchill, the first Duke of Marlborough, and his wife Sarah. Lady Henrietta Spencer-Churchill, Phil’s host, explains that the palace was a gift to the Marlborough family from their friend Queen Anne, a monument to the Duke’s victory over the French at the Battle of Blenheim in 1704. However, in the archive Phil discovers the build was plagued with problems: fall-outs with the architect, unpaid builders and costs beyond even the wildest estimates. Phil tots up a total in today’s money that makes Blenheim the most expensive house he’s ever visited.