Tintin wants to save Didi, the son of Mr Wang Jen-Ghié from madness. For this, he must go, on foot, to Hou Kou. Along the way, Tintin saves a young Chinese boy from drowning: Tchang Tchong-Jen. The latter then becomes his guide and leads him by shortcuts to his destination.
Tintin's new friend points the way, like the real Tchang, friend of Hergé and inspirer of the character, will also do by leading the young designer to beautiful unknown lands, between lessons in drawing, calligraphy and oriental wisdom.
Dressed soberly, a stick in a pilgrim's hand, Tchang smiling makes Tintin discover the splendours of his native land.
A very fine sculpture, as Hergé had drawn, Tchang was reproduced slightly smaller than Tintin. One of the major difficulties of the realization was to make credible the movements of the hair conceived as a simple black solid by the designer in the Blue Lotus.