Wales' castles carry centuries of blood feuds, betrayals, and curses, and this Timeline entry in the Historic Hauntings strand goes looking for the ghost stories that grew out of that history. Historians and local guides walk the ramparts and dungeons of Welsh fortresses, tracing tales of vengeful spirits back to specific acts of treachery: executions, sieges, and family betrayals that locals say left a stain on the stone. The film treats the hauntings as folklore worth taking seriously as history, using the ghost stories as a way into the castles' real violent past rather than chasing scares for their own sake. Expect narration over castle footage, talking-head historians filling in the political context behind each legend, and a steady move from one fortress to the next as the film builds its case that Wales' bloodiest history never quite left its buildings. It sits comfortably alongside other historical hauntings coverage of Britain's older buildings.