As Perverse Magic
You go through the routine with an 'invisible deck" etc explaining how hard it is to get an invisible deck and then have a card named (and comment that card has very rarely been named), pull it out of the invisible deck and insert in face up and then - suddenly - and to the magician's surprize, the deck becomes visible again. "Darn!" you say as you go through the deck and remove the face up named card and put it back face down, "I've got to figure a way to keep the deck visible."
(It's important that the appearance of the deck be done well. Perhaps the deck can be in the right sleeve and, when it's to appear, the right hand drops to the side, the deck is palmed and then the right hand comes over to the left and - all of a sudden - the deck is visible!)