The Vienna Coup may sound like a political upheaval, but it is a bridge maneuver whereby a defender's hand is squeezed and his apparent winners ground up like the meat in a wiener sausage.
The first recorded example of the play dates back to 1864 and the game of whist, the grandfather of contract bridge. As a challenge, a leading Viennese expert of the time laid out a hand at double dummy—cards face up—and announced that he would make all 13 tricks. This appeared to be so obvious an impossibility that large bets were placed against him, but the expert proceeded to fulfill his boast by a method that seemed at first to reduce his chances. He cashed an ace, deliberately establishing the king in an opponent's hand. This, however, set up a position in which the opponent could not keep his king without giving up control of another suit. Indeed, the Vienna Coup is not a simple play to execute, but here is a more recent bridge hand, taken from a team match, in which it became virtually automatic.
South's double of East's obvious sacrifice bid of seven clubs was a conventional warning to his partner. A pass would have been forcing, suggesting that South had first-round control of clubs and was therefore willing to hear North bid a grand slam. But North had reason to believe that his side had not enjoyed the best of the early going and estimated that his team could not win the match by collecting a few hundred points in penalties when at least a small slam would surely be bid and made at the other table. So he went for broke and removed the double to seven spades. His partner's play made the gamble pay off.
West's opening lead of the diamond 10 made it apparent that East held the diamond king, so declarer went up with dummy's ace. He could see that if the heart suit produced five tricks he would be able to discard both of his minor-suit losers. As you can see, the heart suit did not break, but declarer's play of the diamond ace proved to be the first stage of a double Vienna Coup—a play that, by definition, establishes an adversary's card as the highest outstanding in a suit, then squeezes him out of it.
The ace, king and queen of spades were required to draw West's trumps, while East discarded three clubs. Then South tackled the heart suit by cashing the king and queen and on the second round got the bad news that the suit would not run. Declarer could still establish dummy's fifth heart by ruffing, but this would leave him one trick short. Nor would an ordinary squeeze work, because if South cashes all six of his spades, he no longer has a reentry to his hand and East can maneuver to win a trick.
But observe what happens when declarer doubles his Vienna Coup by next cashing dummy's ace of clubs, then returning to his hand by overtaking dummy's 8 of spades to run the remaining trumps. On the lead of the last spade, declarer comes down to the ace-10-8 of hearts in dummy opposite the heart 3, the diamond queen and the club jack in his hand, and East's hand goes through the grinder. He must make a discard from the jack-9 of hearts, the king of diamonds and the king of clubs. If he lets go a heart, dummy's suit will take the last three tricks. If he discards either the diamond king or the club king, South merely cashes his now-established minor-suit winner to turn the grinder once again. No matter what East discards this time, declarer will take the 13th trick with his other minor-suit card or with dummy's long heart.