West has a huge hand – what do they open? It is very tempting to open 2♣  as they pretty much have game in their hand, however, with a two suited had I would opt for 1S. East bids 2♣  and West bids 2♦  (no need for 3D unless you have agreements it shows this kind of hand). After 3♣, 3♦  by West (this should be GF and show 5-5). East could bid 3♥  looking for 3NT, but given West’s 5-5 shape, the likelihood is either no H stopper or clubs will not be much use in NT. As such 4♦  appears reasonable (you could bid 5D showing a weaker had, but those clubs may be huge). After some cue bids where West finds out that the K of spades is missing, west should stop in 5♦  (although as someone known to overbid on slams, bidding 6♦  is tempting opposite a 2 level responder with support).

If clubs are 3-3 and diamonds 3-2, then 6♦  is on. However, with the breaks as they are you need to play carefully to make 5 (on a diamond lead you need to win, ruff a spade, play two clubs discarding spades, ruff a club high, ruff a spade and play a heart, losing a heart and diamond in the end).

There are lots of ways to bid this hand without interference. Do you want to reach slam? It requires two spade tricks and to guess the diamonds, as such it is less than 50% - not the greatest slam. However, that being said, North has a very suitable hand following a 1H opening call by partner and I can understand people bidding it.

The auction is how I would suggest starting (with 2NT being Jacoby GF with heart support, 3S showing shortage and 4♣  being a cue bid). After 4♥  (which denies the diamond ace), it is a case of whether North feels lucky and bids 6H or not. Another option is a splinter, but I would generally reserve that for a weaker (or stronger) hand.

If you get to 6♥, can you make it though on the normal lead of QC?

You have 10 top tricks (6 trumps, 2 club ruffs and the two black aces). You need two more. They can come from diamonds (if the ace and queen are both onside). Spades (if the K drops and they split 4-3). Or a combination of spades and diamonds.

The odds of both diamond honours onside is 25%. The spade finesse alone is 50%. The best play therefore is to play for spades 4-3. Where you are missing 7 cards, there is a 62% chance they will break 4-3. This also gives you the possibility of the K dropping in 3 rounds, in which case you will get 2 spade tricks and need not worry about the diamonds.

In order to maximise your chances in spades you need to manage your entries. As such, win the club lead in hand and immediately lead a spade to the ace. Ruff a spade back and then cross back with a trump. Ruff another spade (unfortunately no K) and cross back with another trump. Ruff the spade again, setting up your long spade.

At this point you have to lead a diamond and it is a guess as to finessing the Q or the A. Here playing the K is right, but not much science here (against some opponents, you may be able to infer that as the Ace was not lead, West did not have it – but see below).

What about the opening lead – should West have led the Ace? The answer is no! Too often that will give away a trick, as would be the case here. Generally leading unsupported aces against suit slams is not a great idea, unless there is a reason to. Occasionally it may backfire if opponents have 13 tricks outside the suit, but in the long run I would advise against it.

The ‘expert’ lead (I am not saying I would find it!) – a low diamond! The K is almost certainly with North (South did not cue bid diamonds), so risk is low and it is a tough play for South to go up with the king on round one.

This hand is all about the bidding. There are 13 top tricks so you want to be in a grand slam.

The first choice is what to open. Whilst North needs very little to make game, when you have a two suited hand you should prefer not to open 2C unless there really is no other choice. As such 1♣ , planning to reverse into diamonds is the clear choice.

After the reverse, South needs to decide what to bid. A very good convention to play is a form of lebensohl, where the bid of the lowest of the fourth suit or 2NT is either a weak sign-off or the start of a forcing sequence (more details below). The usual response to 2S would be a 2NT bid, after which South would intend to bid 3H showing a good hand with 6 hearts (good but not great hearts). However, here North bids 3♦  to show the 6-5 shape and game force.

South shows diamond support with 4♦ , North bids RKCB, South shows 0 or 3 keycards.  North bids 5♦  in case it is 0, South raises as they have 3 and North chooses 7D or 7NT (as it is pairs), chancing that they can pull in five diamond tricks (good odds – 3-2 break, south having the J or guessing the right finesse – better than 50%).

Lebensohl after a reverse (there are other names for this convention)

After the reverse, the lower of fourth suit and 2NT would be lebensohl. In the given hand, the bids for South after the reverse would have the following meanings:

Responses

2H – weak with 5 or 6 hearts – suggesting a sign-off

2S – Lebensohl (see below)

2NT – GF catch-all bid – used when strong with no suitable bid (including with 5H). Partner should make a descriptive bid afterwards

3C/3D – natural and game forcing

3H – strong heart suit (6 cards and near solid), GF

4H – Solid suit

As you will note, all bids above 2S are GF.

Lebensohl bid

2S – asks for 2NT rebid (i.e. next suit up). The 2NT response should always be made unless opener wants to GF

After a 2NT response:

Pass – absolute minimum with no support for partner and stop in unbid suit (e.g. 4522 5 count)

3C/3D – natural weak hands suggesting sign-off

3H – strong hand with good 6 cards suit (but not a good enough suit for direct 3H). Note, weak heart hands will bid 2H as below 2S.

Opener has the choice not to bid 2NT. If they do not bid 2NT, then their bid will be GF and should describe their hand further.