Publisher's summary Edit
London, 1899. After spending time in war zones abroad, Winston Churchill considers a Parliamentary career. But a memento from his visit to Cuba, four years earlier, returns to haunt him. Across the city, the Great Detective has a mysterious caller, all the way from Havana. As ruthless mercenaries wield alien powers, young Winston and Madame Vastra learn they have a mutual friend - an eccentric young man, sporting a bowtie...
- Winston Churchill - Ian McNeice
- Madame Vastra - Neve McIntosh
- Young Winston - Iain Batchelor
- Carmen/Housekeeper - Melody Grove
- Luis Ortega - Owen Aaronovitch
- Reggie/Jorge/Clerk - Leighton Pugh
- Carmen sought out Madame Vastra instead of a pathologist and an impresario or Sherlock Holmes of whom she had also heard.
- The title of the story is a reference to the 1972 film Young Winston.
- This is Vastra's first appearance without Jenny Flint and one of only two appearances without Strax, the other being The Lost Dimension.
- Churchill visited Havana, Cuba in 1895. (PROSE: The Lost Diaries of Winston Spencer Churchill)
- The Eleventh Doctor is described as wearing a purple frock coat. (TV: The Bells of Saint John)