Riko isn’t quite an ordinary child—many basic things are hard for him. “Unusually gifted,” his loving mother calls him. “Idiot,” says the nasty neighbor above. Not many people want to be friends with someone like Riko, but one day he’s lucky: he meets Oscar (a boy who’s also not quite ordinary—a prodigy who, just in case, never takes off a blue motorcycle helmet). And for the sake of his new friend, Riko takes on a case that has been baffling all of Berlin’s police for half a year.