Source: 
Bulletins
In the last article we took a look at the Bath Coup, a common ducking play by declarer. Today’s coup is not quite so well known and, to be honest, opportunities to use it do not come along very often.
West, who overcalled 1
, leads the king of spades against 3NT. The situation in the black suits is identical to the one we saw last time out. Does that mean that declarer should play in identical fashion?
Let’s see what will happen if declarer wins the ace of spades. When East gets in with the king of clubs she will return a spade and down will go the contract. So it must be correct to duck the opening lead, mustn’t it? However, declarer follows with the 8 and West can see that she has just used the Bath Coup so will switch to a heart, and that will see the contract defeated once again.
So is there no hope? The solution is a little sleight of hand. Suppose that declarer ducks the spade lead, but does so by dropping the jack! That is the Pigpen Coup (no bath). If West is taken in and continues spades, declarer wins the ace and takes the club finesse in safety.
It takes a very strong defender to overcome this play. It should always work against people who use attitude signals but, in theory, should fail against people who show count on the lead as West should know that East has only a doubleton spade. Mind you, the only time I ever used it was against a pair of international calibre count signallers, and West got it wrong. He trusted declarer rather than partner.