Two miniature "vaults" are shown. They are actually two beautifully made brass boxes with screw-on lids. The lid and base of one box is silver; the other is red. A female spectator drops her valuable ring into the silver box, screws on the lid and leaves the box in full view on the table. She then places a penny, borrowed from you, into the red box. The box is sealed and also left in full view. If you were a dishonest fellow and wanted to steal the lady's ring, the best way to do it would be to magically swap her ring with your penny without touching either box. That would be the Perfect Crime. The silver box containing the ring is placed on the lady's outstretched palm; the red box with the penny is placed in another spectator's hand. The lady opens her box. Her ring is gone. In its place is the penny. Next, she unscrews the red box to find her ring.