L'oreille cassée (en chinois) Broché

An idol that originally belonged to a Native American nation in South America is stolen from the Museum of Ethnography in Brussels. The following day it is back in the museum, along with a note apologizing for the inconvenience caused, saying that the reason for the theft had been a bet. Tintin, who is among the reporters looking into the story, realizes that the replacement is a fake, the distinction being an ear broken on the original but intact on the replacement.