Wyrd Sisters

After Lancre's king is murdered by his ambitious cousin, three witches—sharp-tongued Granny Weatherwax, no-nonsense Nanny Ogg, and earnest young Magrat Garlick—spirit the infant heir and his father's crown away rather than get involved, or so they tell themselves. Fifteen years on, a troupe of actors staging the usurping Duke's self-serving version of events wanders into Lancre, and the witches discover that noticing things, and eventually acting on them, has become unavoidable.