The Tsar's wife gave birth to a daughter then died. After a year of sorrow the Tsar married again. His second wife was tall, slender, witty, fair to look upon, but also stubborn, willful, proud, and jealous.
In her dowry was a looking-glass, which could speak. She enjoyed talking to it:

"Tell me, pretty looking-glass
Nothing but the truth I ask:
Who in all the world is fairest
And has beauty of the rarest?"
And the looking-glass replied:
"You, it cannot be denied."

She liked the answer very much and began to laugh, mince about, wink, click her fingers and dance before the mirror.
Time went on, the Tsar's daughter grew up and became a beautiful maid. A king's son, Elisey proposed to her, and the Tsar gave his consent.
One day in answer to the Tsarina's usual question the looking-glass said that, no doubt, she was fair but the fairest was the Tsar's daughter. The woman flew into a rage, began to argue with the mirror, but the latter was as stubborn as she and would not change its verdict. The Tsarina could not resign herself to the situation, called her chambermaid and ordered her to take the girl to the forest and leave her there bound to a tree. The servant pitied the maid and let her go free in the forest. While wandering there the young maid came across a house. A dog ran up to her barking, but did not bite her and let her enter. There was nobody inside. She cleaned the rooms, lit the stove and sat waiting for the master of the house to return.
A clatter of hoofs sounded from outside. She became frightened so hid. Seven pink-cheeked and moustached knights came in. They realized that there was someone in the house. "Come out and make friends with us," they said. "If you are an old man, you can be our uncle. If you are a young man, we'll call you brother. If you are an old woman, you can be our mother. If you are a maiden, be our sweet sister." The girl came out, bowed low and apologized for entering uninvited. The men gave her the brightest bedroom, and they all lived happily in the house.
Every morning the brothers would go hunting or sought their fortune in battles while the maiden kept house. They all loved her and one day proposed to choose one of them for her husband; she would remain a sister to the rest. "I love you all, dear brothers, but my heart is to another pledged," she answered. So life went on as before in its harmonious manner.
The Tsarina did not touch the looking-glass for a long time for she could not forget the insult. In the end her craving for flattery prevailed; she took the looking-glass out and asked her usual question. The mirror acknowledged her beauty and added that a more beautiful woman lived in the forest at the seven knights'. The Tsarina guessed who she was and sent her servant dressed as a beggar-woman to kill the girl.
The dog barked at the beggar thus keeping her away from the house. The girl went out with a piece of bread, but the dog would not allow them to meet. The girl threw the bread to the old woman who in return flung a ripe juicy apple back to her. The dog tried to catch it but failed and started howling dolefully. His mistress went on spinning and gazing at the apple which was fresh as if newly picked, red and golden. She took a bite of it, fell to the floor and ceased breathing. The dog fetched the brothers, led them to her chamber, where he seized the apple, swallowed it then died. The young men understood that the poisoned apple was the cause of their sister's death.
They put her in a crystal coffin, hung it with cast iron chains on six pillars in a cave. On that very day the Tsarina asked the mirror her usual question, received the desired answer and regained her peace of mind.
Meanwhile the bridegroom, Elisey, was galloping around the world in search of his beloved. Whoever he asked could not give him any clues as to her whereabouts. The Sun, which observed the whole earth from the sky, had not seen her and the bridegroom to the Moon. The Moon had seen her either. Only the Wind could tell him that she was lying in a coffin made of crystal in a cave. After a long journey he found the cave, threw himself weeping onto the coffin. It broke into pieces, the girl sat up, stretched out her arms and murmured calmly: "Oh, how long I have slept!"
At the same time the stepmother was speaking to her magic mirror, and to her astoundment it ended the answer with "but the princess is the fairest." The spiteful woman could not bear it any longer. She smashed the mirror on the floor and died of grief and envy. After the funeral the wedding was celebrated.

Never since the world's creation
Was there such a celebration.

(Based on Pushkin's "Tale of the Dead Princess and the Seven Knights". English language retelling was done by Vadim Shchanitsyn)