When a world-renowned artist approaches Agaton Sax and asks to have his daily illustrations featured in the Byk?ping Post (the world's smallest newspaper, but also the best) the detective's interest is piqued. Could the detailed patterns and swirls within the pictures hide a secret code? Maybe they will lead to a nefarious plot for Agaton to foil... But is a 113-year-old man really behind it all? And will Sweden's greatest crimefighter...