Answer
You (3rd seat, favorable) are on lead against three clubs:
What’s your lead? You have 18 HCP; give LHO 8-12 HCP and that leaves 10-14 for partner and RHO, so partner probably has one or two useful cards but probably doesn’t have anything more than that. The auction has been at least somewhat informative. With a couple of useful cards and 3+ hearts, partner might not have passed. With 3+ spades, South would have bid spades not clubs. So perhaps the cards are distributed around the table something like this:
North: 5=1=2=5
You: 2=5=3=3 Partner: 5=2=5=1
South: 1=5=3=4
Clearly you won’t lead spades. Probably, it’s best to lead trumps (declarer is likely to be short in spades). What about the red suits? The distribution analysis suggests that hearts probably are South’s long suit, so a diamond lead – though risky – stands to be better than a heart lead. We recommend leading the King of clubs (leading three rounds of trumps might be best, and once we see the dummy, the best continuation may be apparent). We wouldn’t consider any other lead, but – if leading a side suit — the seven of diamonds seem better than any of the other alternatives.
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