The Skeletal Circle is an underground cult of citizens of Shuggazoom City who worshiped the Skeleton King. They are the main antagonists of the titular episode "Secret Society" of the animated TV series Super Robot Monkey Team Hyperforce Go!. This secret society of modern-day sorcerers who practiced black magic, plagued the planet Shuggazoom with their magic powers and sinister curses and continued to serve the Skeleton King, whom they also revered as the divine emissary of the ancient group of cosmic monsters known as the Dark Ones.