We are pleased to be able to offer you Ace Problem, an visual variation of the Hofzinser Ace Problem.
From a deck of cards, the four aces are shown. These aces are placed in a pile, face down to one side. A selection is then made from the deck, for example the king of clubs, then placed under the spectator's hand. The aces are picked up and one by one they magically turn face up in the magician's hands - that is, the first three aces. The fourth face down card magically turns over, however is not the final ace, but the spectator's selection (which is apparently still under their hand). The card in the spectator's hand is turned over and revealed to be the final ace.
Next, the three aces are taken and one by one magically transform themselves into the remaining three kings, so you are left with a four of a kind match of the spectator's selection and one ace. Ends clean and the cards can be examined.
Ace Problem is smooth, direct and visually very magical. Please note that there are a number of sleights required to perform this routine, making it ideally suited to card magicians who have a good technical ability with cards.