As you can see, a diamond lead kills the contract on the spot, but no defender found that killer lead. We were led an innocuous small heart. Now the contract seemed to depend on my guessing the spades right. This I did, but on taking their ♠A, the defence now shot through that diamond. And - silly me - guess what I'd played to the first heart? That's right: the A♥ - so no entry to dummy before the defence come in with A♣.
At the other tables declarers' mistakes were many and varied. But mine was the pits....
Perhaps I need to re-classify myself as "beginner"....