Hitler's dark occult dealings are revealed in the depths of a ruined castle. Plus: a Scottish clifftop bastion with a long history of criminal activity.

A look at Houska Castle, a gothic chapel erected over a supposed gateway to hell and how a property dispute between an eminent family became the catalyst for tragedy. Plus, exploring how a renaissance chateau provided an opulent backdrop for a bitter rivalry between powerful women.

Exploring how, in a castle in Transylvania, the legend of a bloodthirsty tyrant lives on - even after his death. This programme also looks at a medieval Inca castle, where a cursed bounty lies buried. Plus, inspecting a castle on a rugged peninsula, which is supposedly the birthplace of England's legendary king.