Magic Circle

noun

the British association of magicians, traditionally forbidden to reveal any of the secrets of their art
(not capitals) a group of influential people involved in a conspiracy
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012