In a hand of bridge:
Each player has 10 points.
No-one has a pair of Aces.
South holds the QJ.
The Q and the J are in different hands.
East and West are void in the same two suits.
North has a red Ace and no Jacks.
Who holds the K? This problem was given to one of the editors on a train; the original source is unknown. The answer may be found here.