The witness turns on a single purple thread. Nisus, king of Megara, carries "a purple hair on the middle of his head," and an oracle binds his life to it — "an oracle ran that when it was pulled out he should die". When Minos comes against the city with a fleet, it is Nisus's own daughter Scylla who undoes him: she falls in love with the besieger and "pulled out the hair." Megara falls at once, but love earns no tenderness — having mastered the city, Minos lashes the girl "to the stern of the ship and drowned her." The record names the whole ruin "his daughter's treachery."

The tale does not stand alone even on its own page. Sir James George Frazer (1854–1941), the Scottish anthropologist whose Loeb edition of Apollodorus's Library (a Greek mythography of the 1st–2nd century CE) carries this text and its notes, adds in his own hand that a "similar tale is told of Pterelaus and his daughter Comaetho" — another king whose life lay coiled in a bright lock, another daughter who cut it for love of the enemy at the gate. In the apparatus itself, then, the magic hair is already a recognized shape rather than a lone accident.

Only this Greek witness, though, is wired to served text. The record files the same charmed hair across an unusually wide field — Irish, Spanish, French-Canadian, Jewish, and Indian tellings, and a long roll of North American witnesses among them — all still waiting to be read here. What is it that folk memory keeps tying a hero's whole life to the one thread a person who loves him can quietly cut?