King’s Lynn. Friendly isn’t it? But this handsome West Norfolk town has a dark heart. And they say it belonged to a witch. Inside a diamond carved into the red brick above a window of Numbers 15 and 16 Tuesday Market there’s the shape of a heart, said to be the mark of Margaret Read, aka Shady Meg, who was burned at the stake in 1590. As she screamed in an agony of fire, her still-beating heart ripped itself from her chest, slammed into the wall at the marked spot and defying gravity, flew to the River Ouse where the waters bubbled like a cauldron as Meg’s heart sank beneath.

And you didn’t have to be suspected of witchcraft to meet a horrifying end. Found guilty of poisoning her mistress, in 1531 a King’s Lynn maidservant, whose lonely name is forgotten, was wrapped in chains draped over a gibbet above a cauldron of boiling water. She was plunged in, over and over again, until she died. There are only two other records of execution by boiling water in the UK, both at Smithfield in London, and both servants accused of poisoning.

But the real heartbreak is the way a society consumed by fear and superstition launches violent crusades against the most powerless. And the horror is, we still do. Can there really be justice for our murdered ancestors? How did they spend the last hours of their lives? We can at least bear witness to their infinite sorrow.