A bidding challenge - and a card play challenge!

South does better to respond 1♠ rather than jump to the 2-level.  This hand is potentially very powerful and South should give partner as much freedom as possible to make whatever re-bid was originally planned, which in practice would be 2♣. Now South has another difficult bid to find.  3♠ looks tempting, but that is non-forcing, and a fourth suit forcing bid of 2♥ is better.  When North raises to 3♥, South should realise that partner has a 0-4-5-4 or 1-4-4-4 shaped hand, and that message should be enough to keep the partnership out of 4♠, but possibly not out of 3NT.  However, with a bit of a mis-fit, over 3♥ South should abandon any lingering thoughts of a slam and instead plump for 5♦.

At the table, against the more modest 3♦ contract, East led the ♥T, which was won in hand by Declarer.  There are two potential routes to 11 tricks here after a non-trump lead - either a cross-ruff, or seek to set up Dummy's spades.  The cross-ruff requires three hearts, one spade, and then four club ruffs in dummy plus two spade ruffs in hand.  That gives 10 tricks.  If Declarer is very careful with the timing, the lead will be in Dummy at that stage, and when a fourth spade is led West will either concede a third spade ruff or a trump promotion.  However, that line of play fails as the cards lie, because East is able to trump the third heart.

In practice Declarer led the Jack of trumps at trick 2 to West's Ace, and West continued hearts, again won in hand.  Declarer played a trump towards Dummy and East won with the King.  At this point East does best to lead the third trump, but in practice he helped Declarer to find the winning line by switching to spades.  Now it was easy for Declarer to set up the spades and claim 11 tricks.  Even without that defensive lapse, Declarer can still get home.  Win East's trump return in dummy and play Ace and another spade, ruffing in hand.  Cross to the Ace of hearts and ruff another spade.  When the King comes down, Declarer re-enters Dummy via a club ruff, and Dummy is high.

West has a chance to make things awkward for Declarer by switching to a club when in with the Ace of trumps.  That play takes a crucial entry to Dummy out too early, but Declarer can still get home by falling back on the ruffing finesse in spades.

In practice, 3♦+2 scored a 'second top' for NS, because at most other tables Declarers failed either in 3NT or 4♠ or made a spade part-score.