West leads the ♠J. Plan the play
As South, you’re declarer in 3NT (vulnerable at IMPs) against the lead of the ♠J. It looks easy enough: You have seven top tricks, and if you can get two more from the club suit,
you’re home free. Not only that, but there is a safety play in clubs for four tricks even if clubs are 4–0 either way. Just start with the king at trick two from either hand. If clubs are 3–1, you always have four clubs tricks. Furthermore, unless West has Q–10–x, you can make sure that if you lose a club trick, it will be to East. Why is this so important?
Take look at your heart suit. You do not want to expose yourself to losing four heart tricks after giving up a club. If East wins the club, there is no heart holding that allows the opponents to cash four heart tricks. But if West wins the club, and West has the A–10–x or K–10–x of hearts, gets it into his head that four heart tricks are needed to defeat the contract, and makes the killing switch to the ♥10, you’re toast. (In the first case, East has ♥K J 8 x, in the second ♥A J 8 x. Four heart losers.)
So back to the clubs. You can’t keep West from getting in if West was dealt the Q–10–8 or the Q–10–7, but you can if West started with the Q–8–7. Seeing that this is IMPs and overtricks are not all that critical, win the spade lead in your hand with the queen and lead a low club. If West plays the 7 or 8, insert the 9. Say you lose to a singleton 10. You still have four club tricks and East has the lead.
Why not lead the king first to pick up a possible singleton 10 and then lead low to the 9 (the technically correct play)? This is why not: If West started with the ♣Q 8 7, you lose an unnecessary overtrick because East has a singleton 10. If West started with the ♣Q 10 8 or the ♣Q 10 7, however, and plays low at trick two fearing partner has a singleton king, you might have stolen a game when the hearts were stacked against you. It’s worth a try.
West leads the ♣K/ Plan the play and be specific.
Ruff the opening lead, cross to the ♥K and play the ♠Q J. If spades are 4–1, duck a diamond: You need 3–2 diamonds to survive this trump division.
If spades are 3–2, you are looking at about a 90% slam. Ruff a low heart high, draw the last trump discarding a diamond from dummy, cross to the ♦A and play the ♥A, discarding a club. If both follow, ruff a heart setting up dummy’s fifth heart for your 12th trick, using the ♦K as the entry to get back to dummy. If someone shows out on the ♥A, meaning hearts were 5-2, duck a diamond. If diamonds are 3–2, you have 12 tricks: six spades including the club ruff in. dummy, three diamonds, two hearts and the ♣A.
If hearts are 5–2 (or 6–1) and diamonds 4–1, hopefully you will have your partner’s sympathy.