According to certain English folktales, a vile creature lurks in the slime-caked dark of local ponds. When little ones wander too close to shore, she lashes out to drown them in her slippery embrace. She has many names: Nelly Longarms, Peg Powler, the Grindylow... and Jenny Greenteeth. In this episode of Stuff to Blow Your Mind, Robert Lamb and Joe McCormick discuss these old tales of aquatic terror, their instructional nature and the real-world predators who swim the shores in search of terrestrial prey.