You will watch The Simpsons Season 21 Episode 10 – Once Upon a Time in Springfield online for free episodes with high quality. Online episode guide, The Simpsons Season 21 Episode 10 – Once Upon a Time in Springfield. The Krusty the Clown Show is once again reconstructed. This time, in a bid to get girls to watch the show, a princess character named Penelope is hired as Krusty’s latest sidekick. Meanwhile, a corporate recruiter persuades Homer, Lenny, and Carl to work for a nuclear plant in Capital City, after Mr. Burns announces a moratorium on free doughnuts.