Another deal from a Cheadle Hulme duplicate.
North South were playing strong notrump and five card majors, so South opened one club, West overcalled one heart, North bid two diamonds and East raised hearts. South now showed his spade suit and North forced to game by cue bidding the opponent's suit. South had no good bid now, so gave preference to diamonds. North decided that, playing pairs, his best chance of a good score was to play in the four three spade fit. On a heart lead South made twelve tricks for a top score (an unlikely diamond lead is needed to hold declarer to eleven tricks). Most of the other North South pairs were playing a weak notrump so the auction there was one notrump, three notrump. This contract quickly went off.