Who Shot Mr. Burns? (Part One).Springfield Elementary School strikes oil, and plans to spend elaborately. Mr. Burns finds out about the oil and establishes a slant drilling operation to take it for himself. As a result Moe's Tavern is closed, the Springfield Retirement Home collapses, Bart's treehouse is destroyed and Santa's Little Helper is injured, and the school loses all of its money. Burns next decides to build a machine capable of blocking out the sun over Springfield. He fires a recalcitrant Smithers, and Homer vows revenge after Burns repeatedly fails to remember his name. After an emergency town meeting, Burns sets up the sun blocker, believing himself invincible. However, he is shot by an unidentified assailant, and collapses on the town's sundial. Everyone realizes that since Burns angered several people recently, just anyone could have been the assailant. The plot concludes in the seventh season opener "Who Shot Mr. Burns? (Part Two)".