Synopsis by Mark Deming
While Springfield has never been known as a hub of high culture, things hit a new low when local radio station KBBL sponsors a "How Low Can You Go?" Contest, in which the entrant who performs the most humiliating stunt in public wins a trip to Hawaii. A melee ensues, and a disgusted Lisa Simpson (voice of Yeardley Smith) writes a letter to the editor of the Springfield Shopper, proclaiming "we live in a town of lowbrows, no-brows and ignorami." The letter attracts the attention of Springfield's chapter of MENSA, the international organization for people of genius-level IQ, and Lisa is invited to join. When the MENSA members pay a visit to Mayor Quimby (voice of Dan Castellaneta) to complain about the police's handling of park reservations, the wildly corrupt elected official thinks they've uncovered his misdeeds and he his the road. Under a little-known provision in the city charter, the MENSA team takes over the city government in Quimby's absence, but just because they're brilliant doesn't mean they're able to agree on things. Meanwhile, Homer (also voiced by Castellaneta) wins a session with a boudoir photographer, and tries to come up with some spicy snaps for his wife Marge (voice of Julie Kavner), even though the shutterbug warns him "light is not your friend." Featuring a voice cameo from actual genius Stephen Hawking, "They Saved Lisa's Brain" first aired on May 9, 1999.