The bidding: East, with 12 high card points and five spades, opens one spade. Initially, I did not add any points for the spade length or club shortness because partner has not had a chance to bid.
South, with 15 to 18 high card points and three spade stoppers overcalls 1NT. This is the best descriptive bid South has. North with ten points puts the contract into game.
The contract: Three no-trump by South
The opening lead: The seven of spades
West has his own suit, hearts, but he has no entries. Furthermore, he has an obligation to lead partner’s suit. He therefore picks the seven of spades which tells East the seven is his highest spade.
The play: South surveys the situation. He has three spades, one heart and one diamond for five tricks. There are four possible tricks in clubs once the ace is kicked out and more possible in hearts and diamonds. South wins East’s king of spades with the ace. Declarer wants to dislodge the club ace before the opponents find a heart switch. East wins the ace of clubs and plays the jack of hearts because, from the opening lead, declarer has two more spade stoppers.
South plays the queen of hearts which loses to the king and then ducks the continuation. South wins the third round of hearts with his ace.
This cuts communication between the defenders in the heart suit. If East has a fourth heart, then declarer will only lose three hearts and the ace of clubs. If West has a fifth heart, he won’t be able to cash the fourth and fifth heart with no entries.
Declarer cashes his four clubs and takes another spade finesse to claim nine tricks to make 3NT.
The diamond finesse is a source of an overtrick, but cannot be taken because, if East has four hearts, the contract goes down one. If West had five hearts and the king of diamonds, he might have led hearts.
The result: Three no-trump making for +600.