Rauha Räppääjä receives a prophecy that there is a genius in his close circle. Upon finding Risto's drawing, Rauha is sure that Risto is Vincent van Gogh reincarnated, because Risto uses colors quickly and has red hair. Elvik also gets excited about the idea in the hope of success. Rauha decides to present Risto's drawing to the director of the art museum, who offers to take Risto to his home to study drawing. When Risto doesn't hear back from the director of the art museum, Nell and Lennart's suspicions arise. At the same time, a strange coincidence occurs: a sketch of a painting by van Gogh is found in Finland! An exciting series of events starts and takes first Risto and then Nelli and Lennart to a villa hosted by a mysterious couple. But why are Rauha and Elvi suspected of being art forgers? Fortunately, Herkules Poironen, the janitor of the art museum, is an enthusiastic amateur secret policeman and helps Risto and Nelli in solving the riddle.
