This deal comes from my most fertile source--the South Florida Bridge Players Imps Game. With both sides vulnerable, South held: 

A108765
K103
K2
65
After RHO dealt and opened a weak 2, South overcalled 2 (a dead minimum, I'd say). LHO raised to 3 and partner jumped to 4 and you get to play it there.

West leads the 5 and you see:

KQ92 Q92 43 AJ74

A108765 K103 K2 65

You will lose a trick in each minor and the A. It is apparent that everything hinges on finding the J--unless you can somehow find a way to discard a heart on dummy's clubs.

 

East wins the A and returns the Q. At the table, declarer drew trumps (LHO started with a singleton J) ending in hand. He tried a club to dummy's jack. If LHO had the KQ, this would immediately solve all problems. Even if it lost, declarer expected to be able to get a count on the hand.

 

The J lost to East's queen and a club came back. Declarer won the A and ruffed a club--East throwing a diamond. Are you counting? East started with Qx, 2 trumps and likely 6 diamonds. This means hearts are 4-3 with West having 4. Accordingly, declarer went with the 4:3 odds and finessed against West in hearts. This was the Real Deal: 

Vul: Both Dlr: East	KQ92 Q92 43 AJ74
J A854 1065 K10832		43 J76 AQJ987 Q9
	A108765 K103 K2 65

True, it was unlucky that the hand with only 3 hearts happened to have the jack. However, there was a much better line of play available. After winning the K, declarer should cash the A, draw trump ending in hand and lead towards dummy's J.

 

Do you see the extra chances? If West started with the KQ, declarer is still okay; Upon winning a high club, West will have to either break hearts, issue a ruff-and-sluff, or lead from his other club honor (setting up dummy's J).  If clubs prove to be 4-3 with nothing interesting happening, that means East started with 2 spades, 6 diamonds and at least 3 clubs--making it very likely West has the J. Best of all is that clubs will often be 5-2 (as in the Real Deal). Look what happens on the second round of clubs. East has to win his Q and is immediately endplayed into breaking hearts or issuing a ruff-and-sluff. 

This superior line of play was missed at both tables in this expert game.