South opened One Spade, North responded Two Diamonds, and South rebid Two Hearts. North explored with Three Clubs (the fourth suit), and South showed his strength by jumping to Four Hearts. This seemed to interest West (perhaps, inadvertently, warning South of dangers ahead?) but North now advanced to Six Spades and all passed.
In view of his hold in hearts, West should have led a trump but chose the queen of clubs. After winning on the table, declarer led a heart to his ace but, before trying a second heart, crossed first to dummy with a club. Then came the next heart. East discarded (best) and, after winning, declarer led a low heart and ruffed with dummy's nine. This would have succeeded if West had started with the ten of spades and the suit broke no worse than 4-2. As it was, East over-ruffed with his ten and returned a trump to leave South a trick short.
A better plan would have been to ruff the third round of hearts with the ace of trumps and come back to hand with the ace of diamonds and a diamond ruff. Then the ten of hearts can be ruffed with dummy's nine. If East over-ruffs, declarer's hand is high; while, if East discards, South can score with his last low trump. In that way his only loser is the fifth heart which East is able to ruff.