Gone Maggie Gone

S20, E13: In this satire of the DaVinci code, a rare solar eclipse temporarily blinds Marge. Without her in charge, the kitchen is taken over by rats, and when Homer gets poison to kill them, he must briefly set Maggie down outside a convent, where the nuns take her in and refuse to give her back. Trying to recover her sister, Lisa uncovers a plot to bring everlasting peace to Springfield, involving a mystical gem, the founding fathers, and Principal Skinner's mother's minivan.