Keepers of the Realm by Lyn Willmott
Approx. 111,860 words.
Published on January 25, 2010.
Set in The Kimberly, Australia; Keepers of the Realm brings together an ancient people - who have hiden their kingdom from Mankind for thousands of years - and a group of environmentalists who join these Aliens in an attempt to alert Mankind to the imminent danger facing the planet. Once discovered, the kingdom comes under attack from the industrial/military complex threatening Earth's survival.