Purim, Judaism's strangest holiday (which this year falls on March 20), is prescribed by what may be the strangest book in the Hebrew Bible, the scroll (m'gilah) of Esther. Two public readings of the book, one at night and the other in the morning, tell a story of Persian palace intrigue in the fifth century B.C.E., a recitation accompanied by the holiday's decidedly unspiritual noisemaking, tippling, and masquerade.