Rainbow Dash and Twilight Sparkle visit the Cloudsdale Weather Factory seeking to understand the extreme cold weather across Equestria. Town weather ponies are tired of receiving complaints, and frustrated by the lack of answers from higher up. Rumours circulate that a mysterious monster—a polar vortex—has seized control of the North and threatens Equestria. They get passed from office to office, as each branch of the Weather Factory denies responsibility, as they pursue their quest to understand the mechanisms controlling the Equestrian climate.