Movie #9 : page 3

Where is the ♣A?  If partner has it, then it is a simple matter to grab the ♥K and take a club trick later; it cannot get away.  Yet, just as a diamond signal could be disastrous from partner's perspective, a club discard at trick three could be fatal in a layout where there is no heart loser:

If west throws a club, the suit comes home with one ruff, and the hand is over.  However, partner does not have the ♣A, for two reasons.  One clue is that declarer did not arrange to win the third trump in dummy so as to lead clubs toward his hand — an automatic procedure.  A more reliable indicator, however, is once again indicated by partner's carding in the heart suit.  Holding the ♣A, she would have played the ♥2, then her second-lowest (6 or 7), in suit-preference fashion.  Her actual heart plays were non-committal, indicating no preference.

Okay.  Partner has no aces.  But where are declarer's ten tricks?  If south's clubs are as good as ♣AQJ and he guesses to finesse in the right direction, then nothing can be done.  Additionally, if his pattern is 4-2-3-4, then he can discard a diamond on dummy's hearts and ruff out that suit for another trick.

If declarer has a singleton diamond (4-2-1-6), then he probably would have played on clubs, not needing to lose a heart.  Also, partner probably would have discarded her idle fifth diamond at trick three, having nothing much else to say.  So you assume declarer to be 4-2-2-5.

But you have yet to play to the heart lead at trick four, and your opponents are beginning to stir uncomfortably.