In exchange for Fujiko's life, Lupin steals a crown from a fountain of concentrated sulphuric acid. This is actually a test of skill: the real objective is to show snow to Princess Guiana, of the country of Iraran. The little princess doesn't have long to live. The only way to make snow fall in the desert is to acquire the Snow Cannon from Spinar, the world's most powerful secret society. Will Lupin make it in time?