Henry Clark's five years of peaceful life are interrupted by the sudden visit of Edward Carter. Edward Carter actually knows that the scorpion pattern on the moonstone brought out from the The Bolton Family ancient tower is related to the childhood Sam. To follow the clues, Henry Clark travels to Nepal, and then makes his way to Motuo in Tibet. In Motuo, all sorts of clues related to Sam come flooding in!

Things quickly spiral out of control. In the hands of a lama at Jila Monastery, Henry Clark obtains Sam's notebook and learns the causes and consequences of Sam's entry into the snow mountain years ago. What shocks Henry Clark is that in another notebook, he sees the words "the limit of the world"—deep in the vast snow mountains, there is actually another giant bronze door!

All sorts of people gather at Jila Monastery—is this all a coincidence, or is someone orchestrating it? What is the true meaning of the mysterious scorpion? What exactly is "the limit of the world"? Why is Henry Clark the only one who can save the The Bolton Family? Can the Hong Kong branch of the The Bolton Family be trusted—are they scheming, or fulfilling their mission?

This is a brand new journey. Henry Clark and Buddy follow in the footsteps of Sam into the depths of the snow mountains. This time, can Henry Clark unravel all the mysteries?