With the trapping trade on the decline, mountain man Barnaby Skye takes work as a guide, leading a wealthy Englishman, Graves Duplessis Mercer and two companions on an exploration of the Yellowstone and Missouri River valleys. Mercer is a peculiar employer. He has come to the American wilderness seeking weird, morbid, thrilling, and preferably slightly salacious, material to write up for British tabloids. He has little interest in such amazing natural phenomena as the geysers of the Yellowstone country but is adept in ferreting out stories of cannibalism and similar atrocities. To the Britons disappointment, Skye has none of these to offer but agrees to take him to a Missouri River valley where gigantic bones of ancient monsters are thrust out of canyon walls. Skyes Crow Indian wife, Victoria, warns that the bones are sacred among certain tribes, but Mercer insists on taking a trophya tooth from a tyrannosaurus-like fossil. This act nearly costs the lives of Mercers party and its guide, Barnaby Skye. Wheelers Barnaby Skye, a deserter from the Royal Navy who becomes a legendary mountain man, has been called the Horatio Hornblower of the Rocky Mountains.