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.