While Sheldon obsesses over Pluto's planetary status (a microcosm of his own fear of demotion), Missy is discovering the scarier physics: . She stands in two places at once—the good daughter and the rebellious teenager—like a particle that changes behavior when observed.
In the end, Sheldon successfully recovers his lawn gnome, and the neighborhood comes together to discuss the importance of respecting each other's property. The episode ends with Sheldon back in his laboratory, pondering the intricacies of human behavior and the importance of lawn gnome security. young sheldon s05e17 720p web h264