SKUL

SKUL is an evil organization engaging in criminal as well as terroristic activities and the main rivals of M.I.9 in M.I High season 1-5. In season 6 they are destroyed by another criminal faction called KORPS. Their leader is a shadowy man who is referred to as the Grand Master.

History
SKUL didn't start as it's own organization. In fact SKUL was a division of the bigger terroristic organization KORPS. But one day the Grand Master betrayed KORPS to M.I.9 so that he could get SKUL to break away from KORPS and so he could run it himself. SKUL grew and grew and evenually turned into a successful, influencal and powerful criminal organization in the United Kindom. SKUL does all sorts of crimes ranging from bank robbery and kidnapping to trying to make war or destroying the moon. Through season 1-5 SKUL was the main and most dangerous enemy of M.I.9.