From epubbooks.com:
Sitting beside entrancing Lady Ragnall while the smoke of an ancient Egyptian herb grows thick around them, Allan Quatermain finds himself departing the world he know and entering into his strangest adventure. In a mystic transformation, he comes to his senses in an earlier incarnation . . . as Shabaka, hunter of lions – scion of the rulers of ancient Egypt, and lover of the Lady Amada, the Priestess of Isis