Solution to Christmas Prize Quiz Hand

After a straight forward auction, west leads the heart 5. You have 7 top tricks (2 spades, 1 heart, 4 clubs) and 2 more from forcing diamonds. Is there a 100% line of play?

If hearts break 4-3, the hand plays itself for 9 tricks, so assume a 5-2 break. One line would therefore be to hold up at trick one and win the heart return in dummy at trick two, leaving east void.  If east also holds the diamond ace, the contract is safe.  That's about a 50% shot and could work on many hands.  Let's be honest: many of us would do that instinctively in a 7-minute per hand session.  However, given 30 days to ponder, can we do better?

It's always worth noting who holds what in the top five honours (hearts here):  we hold A10, so EW hold KQJ.  If west held KQJxx, he would have led K and not "4th highest from an honour(s)".  That means east must hold either doubleton Hx or HH.  If we rise with our heart ace at trick one, east will be left holding either singleton H or just x.  Either way, when we now knock out the diamond ace, the heart suit is blocked, regardless of who holds diamond ace.  On this layout, at trick three, east can win his heart J, but has no heart to return.  Alternatively, west can cash his heart KQ, leaving declarer's heart 10 as a second stopper after east's jack is crushed.  It's no better if east unblocks his jack on the ace at trick one, the 10 still becomes a potential stopper.

Well done to Ray Cole and Geoff Cordingley who both spotted the 100% line and therefore receive £4.00 credits each. Reasonable alternative lines were submitted by Richard Lord and Sheila King, each receiving £2.00 credits.