However , Chief Wiggum suddenly appears during the show and arrests Bart for covering the town in graffiti .
Street artist Shepard Fairey encounters Bart one night and offers him a gallery show of Bart 's artworks .
Chief Wiggum suddenly appears during the show and arrests Bart for covering the town in graffiti .
Street artist Shepard Fairey encounters Bart one night and offers him a gallery show of Bart 's artworks .