Based on the improbable true story of the last woman found guilty of being a witch. Helen knew all of the tricks: the trances, the seances, the ectoplasm made of cheese cloth. As performing mediums go, she wasn't half bad. When people want to believe, it doesn't take much, after all. But this time felt entirely different. It was the height of WWII in England and this time images of the ship going down - the massive, earth-rattling explosion, the faces of young, terrified sailors sinking to their death – this time, it was like she was actually being haunted. And when word got out, she didn't just attract crowds of the sailors' family members. She caught the attention of Winston Churchill himself. Helen was describing, in extraordinary detail, the highly classified sinking of the HMS Barham, a military secret guarded with extraordinary care. As the invasion of Normandy was secretly being planned, fear swept through the administration that Helen Duncan, the prickly Scottish mother of 6, might actually have the power to predict and to reveal details about the invasion. So, to silence her, she was hunted down, arrested, tried and jailed... for being a witch.