In 1934, when Zhang was studying at the Academie Royale des Beaux-Arts in Brussels, he was introduced to Herge and helped him with The Blue Lotus.

"With The Blue Lotus I discovered a new world," Herge told French writer Numa Sadoul in 1971. "I was learning about a civilization I knew nothing about, while at the same time becoming aware of the need for a certain degree of accountability. From that point on, I set out to really research and take an interest in the people and countries I was sending Tintin to explore, so I could present them honestly to my readers. I owe it all to my meetings with Mr Chang, who also gave me a better understanding of the meaning of friendship, poetry and nature," Herge added.

Their friendship continued and is still of great significance to the establishment of diplomatic relations between Belgium and China, as well as with the rest of the world.

"With the joint efforts of these two young artists of the same age, The Blue Lotus－the great masterpiece in the history of the world's comics－was born," says Bruno Jans, consul general at Consulate General of Belgium in Shanghai.

"It stands for cultural exchanges and the friendship between China and Belgium from as early as the 1930s."

"In Belgium, we say that readers of Tintin are 7 to 77 years old, meaning that anybody can enjoy reading Tintin," Jans adds. He is a case in point, having read the comic when he was 7. He believes that many European readers first learned about China by reading The Blue Lotus.

"This friendship not only symbolizes the friendship between China and Belgium but also symbolizes the friendship among the people of the world," he says.

Today, Tintin is 92 years old. But he is still a well-known hero, influencing the childhood of younger generations.

"Tintin is a brave, friendly and adventurous person. He went to so many countries, met so many friends and experienced so many adventures. The textual research of all the details was not accidental but formed by a series of efforts," Wang says.

"Although the author died in 1983 and no new stories have been created, this comic is still popular that today, in 2021, there are still many people who love Tintin," Wang says.

Contact the writer at heqi@chinadaily.com.cn