1. A visual puzzle comprising: a plurality of partial image sheets, said sheets of a transparent material and having partial image portions of a first color and background portions of a second color formed thereon, said partial image portions and background portions formed on both sides of at least one of said partial image sheets, said image and background areas forming a first image or a second image when properly arranged in corresponding overlying relationships, said image portions and background portions formed on said partial image sheets by selectively masking portions of said first image with either said second image or other partial image sheets or both so that said image portions and said background portions are codified onto said partial image sheets.