In Guy Boothby's novel 'A Cabinet Secret', set in Naples, the story begins as two men are waiting anxiously for a private steam yacht, the Princess Badroulbadour, to arrive in the harbor. They are conspiring to bring down one of the greatest empires, and the Princess carries with her an important key to their plan. This thrilling novel takes readers on a journey of conspiracy, deception, and suspense as the fate of an empire hangs in the balance.