This is the second story in the Tarzan adventure novels. Tarzan has been in England where he has been learning about civilization, his heritage and how he fits into it all as Lord Greystoke. Fate thrusts Tarzan back into the primeval jungle and as he returns to it, his adventures begin with a shipboard altercation. Evil Nickolas Rokoff, the recipient of Tarzan's wrath, swears vengeance and puts a price on Tarzan's head. But Tarzan has greater concerns on his mind as he leaves modern civilization behind to discover a hidden ancient civilization.