This Real Deal was defended beautifully by Sjoert Brink in the semifinal of the 2022 World Championships:

As West, he held:

752
KQ863
3
10762

On lead after 2 P 4 (All Pass), he led his singleton diamond:

Vul:Both Dlr: South	J4 A1075 AQ6 AQ94
752 KQ863 3 10762

Declarer played the Q and East won the K and returned a lowish-looking diamond, ruffed by West. Now what?

Here is the full deal:

Vul:Both Dlr: South	J4 A1075 AQ6 AQ94
752 KQ863 3 10762		K8 94 KJ10752 K83
	AQ10963 J2 984 J5

According to the double-dummy analysis, 4 can't be defeated. Because of all those useful jacks, declarer can handle any return. With the aid of the spade finesse, he can draw trump and lose only 1 trick in either clubs or hearts. Suppose West returns a club at trick 3? Declarer wins the ace and leads the J. After trump are gone, he plays the J to set up a discard for the heart loser.

What if West exits with the K? Now, declarer wins, draws trump and plays a heart to set up a discard for the club loser.

But declarer didn't know what we know. Brink played a low heart at trick 3. He knew declarer couldn't afford to duck this (from South's point of view, East would win the heart and issue another diamond ruff). Sure enough, declarer went up with the A at trick 3. He drew trump, but could no longer make the contract (having to lose a trick in both clubs and hearts).

At the other table, North was declarer and was never challenged, emerging with an overtrick for +650 and a 13-imp swing.