SKUM was a criminal organisation that was founded and run by the Grand Mistress as a splinter faction of SKUL. The name is an acronym that stands for "Superior Krew for Ultimate Maximization". It featured in the second M.I. High game, "Catch The Grand Mistress".
In "Catch The Grand Mistress" the M.I. High team receive a cryptic message from a mysterious stranger, who is later revealed to be the Grand Mistress, having escaped from prison. The team attempt to track her down but every time they find her she gets away. The Grand Mistress frequently transmits video messages to one of her SKUM agents (who is a mole inside M.I.9) which the team intercepts and de-codes in order to find her location at a secret base inside the Kingsway Telephone Exchange in London.
- Brain Freeze Ice Cream
- SKUM Airlines
- Whoozle Bang Toy Company
- Headquaters: Appears in "Catch The Grand Mistress". Located deep within the Kingsway Telephone Exchange in London. The Grand Mistress regularly sent encrypted video transmissions to her mole inside M.I.9 from here.
- Grand Mistress: Leader of SKUM
- Remote Animatronic Tactician (RAT): robot