Didi saved Tintin's life from a drive-by assassination attempt after leaving Mitsuhirato's fashion store upon first arriving in Shanghai. He was poisoned by Rajaijah Juice, causing him to go insane and develop a fixation with chopping off people's heads, saying it would help them find the way. He almost killed his father, his mother, Snowy and Tintin while they were captured by Roberto Rastapopoulos and Mitsuhirato. He would also occasionally go running up and down a hall with a drawn sword, yelling some Martial Arts yells. He finally gets his revenge for stopping him from killing Tintin, Snowy, and his parents. Suddenly, Chang fired his gun at Didi's sword, and Didi was angry for his failure to kill his parents, and Tintin. He was later cured by Professor Fang Hsi-ying's antidote and regained his sanity.