It would be reasonable to lead ♣K, attempting to set up a Club trick while you still have the ♠A entry.  But the bidding around the table suggests extreme distribution, and perhaps there is a singleton Club somewhere (probably in the South hand).  A more promising plan might be to lead the singleton Heart, later winning the ♠A, then underleading the ♦A to East’s hoped-for ♦K, and getting a Heart ruff for down one.  Nice lead!  It turns out that Partner does indeed have the ♦K and that neither North nor South has a Diamond void.  Does that mean that 5♠ is down one?  Not necessarily, because there is a clever counter-measure.  Now put yourself in the South seat and see if you can deprive West of his ruff.

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