While Sherlock Holmes solved the mysteries of London, someone else kept the city safe from the shadows.Mrs. Hudson was no ordinary landlady: she was the Master Key of a secret network of women controlling access to important homes, embassies, and palaces. Landladies, maids, and housekeepers wove invisible messages, thwarted conspiracies, and protected lives-all from kitchens, basements, and laundries.In this fascinating story, told by the faithful Dr. Watson, you will discover how the Society of Keys: Protected state secrets while London slept.Neutralised assassins and spies without anyone knowing.Trained new generations to ensure the city remained safe.An adventure blending thriller, historical espionage, and female empowerment, showing that the true power of London was not always found in the streets, but in those who knew how to open doors others could not even imagine.Who really ruled London in the Victorian era?Find out behind the tablecloths, the keys, and the kitchen of 221B Baker Street.