Intervention sets the scene for Julian May's new trlogy of the Galactic Milieu. This has been split into two The Surveillance (containing Prologue, The Surveillance, and The Disclosure) and The Metaconcert, containing The Intervention and Epilogue.For 60 000 years the five races of the Galactic Milieu have watched and waited for the time when human mental development on Earth is ready for the Intervention...As the twentieth century draws to its end, phenomenal mental powers are displayed by 'operants' all across our planet... They can 'farspeak' one another telepathically. They can build mental shields and they are capable of coercion by power of mind.One of there is Rogatien Remillard, a dealer in secondhand books, whose memories - written a century on - form the core of this chronicle. They tell of a world where the mind has become a weapon; and of two brothers, each possessed of extraordinary powers - one a peace-bringer, the other an advocate of evil...