Dot's Net - Multiplying Dot Card

A jumbo card is shown to the audience. It has one spot on one side and four on the other. It is shown again to have three spots on one side and six on the reverse. The magician proceeds to explain to the audience how the trick is done and everyone thinks they understand – that is until they find out that they have been fooled. The real surprise is when eight spots appear on the reverse side.

aka What's Next?