You will Watch Scooby-Doo! Mystery Incorporated Episode 23 online for free episodes with HQ / high quality. Stream cartoons Scooby-Doo! Mystery Incorporated Episode 23 Fred’s dad is being attacked in his home by an unknown shadowy figure, and the gang has to get to the bottom of the mystery. The gang discovers a second puzzle piece that the mayor is hiding, and finds that Pericles is the one responsible for the attacks on the Mayor. When asked about the mayor’s puzzle piece, Pericles states that the mayor stole it from him a long time ago.