The band Green Day holds an environmental concert in Springfield, but it ends in dismal failure, with members drowning after falling into the water. A mass is held at the church to mourn them. The Simpsons arrive late again, and Grandpa suddenly becomes possessed, prophesying an impending disaster. Bart is punished for skateboarding naked and receives help from his neighbor Flanders, bonding like father and son. Lisa meets Colin, an Irish boy who shares her ideals, and the two develop a budding romance. Homer's disposal of nuclear waste and trash severely pollutes the water supply. He brings home a pig, much to his wife Marge's displeasure, though their youngest daughter Maggie enjoys it. A bizarre creature covered in countless eyes makes everyone realize the severity of the problem. At the town meeting, Lisa's environmental proposal is rejected, and the issue reaches President Schwarzenegger. The government orders the heavily polluted Springfield to be quarantined. Only then do the awakened townsfolk understand the importance of the environment, and the angry crowd turns its fury toward the ones responsible for the pollution—the Simpsons family...