The Simpsons (1989): Season 37, Episode 14

37 - 14: Irrational Treasure

Marge's crusade to get the family dog in better shape leads to her entering Santa's Little Helper in canine agility competitions and a trip to the National Dog Show in Philadelphia. There, Marge and Homer suddenly find themselves - and the dog - mixed up in a historical conspiracy adventure worthy of a "National Treasure" movie.