The short story takes place in a land ruled by a semi-barbaric king. Some of the king's ideas were progressive, but others caused people to suffer. One of the king’s ideas was a public arena using a trial by ordeal as an agent of poetic justice. Either crime was punished or innocence was decided by the result of chance. When a person was accused of a crime, his future would be judged in the public arena before two doors.[1] Behind one door is a lady whom the king has deemed an appropriate match for the accused; behind the other is a fierce, hungry tiger. The accused is compelled to select a door. If he chooses the door with the lady behind it, he is innocent and must immediately marry the woman, but if he chooses the door with the tiger behind it, he is deemed guilty and is immediately devoured by the tiger.
The king learns that his daughter has a lover, a handsome and brave youth who is of lower status than the princess. The king does not shirk from his duty to hold a tribunal, and the princess' lover is thrown into prison to await his trial in the arena. The princess, meanwhile, through intrigue and influence, discovers which door conceals the lady and which door conceals the tiger. Once in the arena, the accused looks to the princess for help, and she discreetly signals for him to choose the door on the right, which he does. However, it is unclear whether she has sent him to his death or to a marriage with a woman she resents as a rival.
The author then departs from the narration, summarizing for the reader various facts about the princess' state of mind and her attitude towards the woman the king chose for the arena's door, and challenges the reader to decide which door the princess indicated for her lover. The story ends with the famous quotation: "And so I leave it with all of you: Which came out of the opened door – the lady, or the tiger?"
Source: Wikipedia

Read the whole story and decide for yourself.