The Simpsons
Rednecks and Broomsticks (21x7)
:
After getting lost in a game of hide-and-seek, Lisa wanders into the field and discovers three teenage girls who are practising Wiccans. Though she is sceptical of their spells, the girls assure Lisa that they never hurt anyone and ask her to join their coven. Just before Lisa is inducted into their pact, Chief Wiggum arrives and arrests the three girls for witchcraft and Lisa becomes the star witness in the trial.