Here is the best version of the classic 4 Queens (or 4 Jacks) packet brainwave effect.  It seems to have eliminated the weak points of the trick, and at the same time, make it even more effective.

A packet of cards is displayed on a small stand.  A spectator names any one of the 4 Jacks, say, Jack of Diamonds.  Performer spreads the cards on the stand and only the Jack of Diamonds is facing the audience.  This card is taken off the stand to show that it also has a different colour back.

Finally, the remaining 3 cards on the stand are turned around to show that they are the three 4’s of the non-selected suits, niz 4 of Spades, 4 of Clubs and 4 of Hearts.

You are supplied with a special stand, 4 specially printed playing cards, and printed instructions.

When Max Maven came up with his “B’Wave”, his brilliant use of the blank cards not only eliminated a major weak point of the 4 Queens brainwave trick, it gave a separate climax as well.  Hideki Tani’s ingenious use of the small card stand plus the special printed cards brings the B’Wave to an even higher level.  Now, any one of the 4 Jacks can be shown reversed, plus the other 3 non-selected cards can be shown to be the 4’s of the non-selected suit.  Two of them can almost be shown full face-on to the audience.  The handling of the cards is casual and above-board.

It will be hard, if not impossible, to find another version of the 4 Queens (or 4 Jacks) brainwave trick that can top “Jack 4 You”.  (9/10 stars rating.)