Who was that?' asked Clara. 'And what are pieces of eight?' The Doctor smiled. 'Robert Louis Stevenson. I did tell you.' Summoned to 1700s Plymouth, the Doctor and Clara must investigate a mysterious thievery from the Crown of King George. Their travels take them to a remote island - but as the secrets of the theft are unearthed, the Doctor discovers something far more sinister. The spectre of a terrible intellect is afoot. Thankfully, the Doctor and Clara won't be alone. A pirate called Long John Silver, a runaway called Janey Hawkins, and professor called River Song, are all along for the ride.