The secret is to hitch a ride to dummy with an opponent. Win the ace of diamonds and cash the ace of trumps, noting that both opponents follow suit. Only the queen is missing but you don't draw it. Instead you cash your 3 black winners before leading a low trump in the hope that it is East who has the last trump. You know from the weak 2 that East has no more diamonds so on winning the queen of trumps he will have no choice but lead a black card allowing you to discard your 2 losers.

Kate McCallum, who played the hand, said it was a revelation to her to see that you could gain a trick by losing a trick.