Tintin is enjoying a vacation with the Maharaja of Gaipajama. One day a Chinese man comes to meet him but is hit by a dart dipped in a poison which causes madness (Rajaijah). He just had the time to tell him that someone going by the name of Mitsuhirato wants to meet him in Shanghai. Tintin travels to Shanghai, China, where he is awaited by the assassins of the opium consortium.