Shortly after the fourth Duke of Portland died in 1854, the fifth duke began construction of a fantastic underground palace beneath the family's estate. Was it a physical representation of a secret underground life he was living as a London businessman with two families? In this work of historical detection, the authors reconstruct a century of controversy surrounding the Cavendish-Benticks, culminating in one of the most bizarre and publicized cases the British courts have ever seen. A man steeped in layers of deliberately manufactured mystery, the fifth Duke of Portlandunmarried and childlessstarted life as Lord John Bentick, became the Marquess of Tichfield upon the suspicious death of his elder brother, and passed on his title to a cousin when he perished in 1879. But some claimed that he had forged a second identity as Thomas Druce, owner of the Baker Street Bazaar and subject of countless rumors about his secretive lifestyle throughout British high society. Druce allegedly died in 1864, but his burial produced suspicion when it was claimed his coffin was filled with lead rather than a corpse. When Druce's daughter-in-law surmised that he might have survived for 15 more years, she set out to shake the foundations of British society by proving that her son, Sidney Druce, was the rightful heir to the dukedom. In a legal battle straight out of Alice in Wonderlandwith accusations of madness, perjury, and even grave robbingthe previously unassailable aristocratic establishment threatened to topple. The Disappearing Duke is a most extraordinary and improbable tale that will delight history buffs, mystery lovers, Anglophiles, and anyone who delights in the absurd. An index with sources is included.