West   North   East   South
                                 1♣
pass     1♠       pass    2♥
pass     3♥       pass    4♦¹
pass     4NT²   pass   5♣³
pass     5♦⁴      pass   6♥
all pass

1 - cue-bid
2 - RKC Blackwood
3 - 0 or 3 keycards
4 - asking for the trump queen

Not the most elegant auction, but the final contract is a sound one. West leads a diamond, dummy's queen holds. Plan the play.
Solution:
After winning the first trick with the ♦Q, the plan should be to play a heart to the ten, followed by a heart to the queen. When you play a heart to the ten, it holds. The correct play now is to cash the ♣A, and ruff a club in dummy.

East, who started with four hearts and one club, is helpless. If he discards, you play a heart to the queen, cash the ♥A, and keep running clubs. If he overruffs and say he returns a diamond, play a spade to the ace, finesse the ♥Q, cash the ♥A drawing the last trump, and claim the contract.

While regular readers of this column may feel that the play to this deal is routine, the actual declarer made the mistake of cashing two top clubs; East ruffed and returned a diamond, after which the slam could not be made.

Analysis:
An opening spade lead or club lead is required to defeat the slam. Once a diamond has been led, declarer has to follow the recommended line of play to make the contract.
Par Contract Analysis:
The par contract on this deal is 5♥ By North-South.

Bridge Baron deal No : N3587-37872-61569-88446-55313-83025