There are more than one artists with the name Illegal Substance:

1) A rap/electro/rock group from the US
The retro-electro group Illegal Substance is a collaboration of childhood friends P-Nut, and Wren, aka Captain Handsome. From the start, the concept for creation was simple, don’t set genre or musical boundaries. They combined addicting elements of electronica, hip hop, 70’s rock, retro 80’s synth pop, and anything else they could get their hands on. With a plethora of influences, and an alacrity to stand out, Illegal Substance has branded their own form of unique. The group’s maiden voyage was the self-titled album Illegal Substance, released under Moonshine Music in 2003. It featured the heavy electronic driven “Step to the Floor” and “Microphone Check”. With Punny Rico as their new label, Illegal followed up in 2007 with a full length album entitled Bachelor Party. It featured the anthem “Panty Raid”, and the unforgettable bass groove of “Banana Song”. The B-Side Bonanza was released in 2008 as a collection of popular remixes, instrumentals, and a few originals. With a return in 2010, Illegal Substance released the pop synth single “Strip Tease” which was followed by the politically charged “Neutrality” in 2012. 2014 has brought the electro-disco single “Neon Light”, which has a guest appearance by talkbox specialist Lloyd Popp. Illegal’s full length album is due out in late 2014.

2) A Rap group from Sydney Australia
Illegal Substance was a rap group from sydney that released the album "Off Da Back Of A Truck" in 1994. the members of the group were Micke, Flip & E.S.P. Read more on Last.fm. User-contributed text is available under the Creative Commons By-SA License; additional terms may apply.