A corner of a spectator selected and signed card (no force, no exchange of the card or corner) penetrates the glass of a wrist-watch.

The effect and the method of this trick are incredible. Normally you would think that an effect like this would involve a forced card, or a secret exchange of the torn corner. But this effect uses neither. You start with a completely fair and free selection of a card. The card can be signed and marked all the way into the corner that will be torn off. Then the magician tears off a corner of the card. And that corner will penetrate the watch glass. The corner is never exchanged. The spectator could after the effect destroy the watch, take out the corner and check if it is the corner from his selected card. He will find that it is.

This effect requires sleight of hand and the wrist-watch needs to be prepared. The preparation does work with many different watches, but there will be some that will not work. The video will show you which ones are best suited for the effect.