The sequel to "New York Times "bestseller "Below Stairs," "Servants' Hall "tells a gripping real-life tale reminscent of "Downton Abbey's" Lady Sybil and Tom Branson. Margaret Powell's "Below Stairs "became a sensation among readers reveling in the luxury and subtle class warfare of "Masterpiece Theatre"'s hit television series "Downton Abbey." Now in the sequel "Servants' Hall," Powell tells the true story of Rose, the under-parlourmaid to the Wardham...