Twelve princesses, each more beautiful than the last, sleep in twelve beds in the same room; every night their doors are securely locked, but in the morning their shoes are found to be worn through as if they had been dancing all night. The king, perplexed, promises his kingdom and a daughter to any man who can discover the princesses' secret within three days and three nights, but those who fail within the set time limit will be put to death.
An old soldier returned from war comes to the king's call after several princes have failed in the endeavour. Whilst traveling through a wood he comes upon an old woman, who gives him an invisibility cloak and tells him not to eat or drink anything given to him in the evening by any of the princesses and to pretend to be fast asleep until after they leave.
The soldier is well received at the palace just as the others had been and indeed, in the evening, the eldest princess comes to his chamber and offers him a cup of wine. The soldier, remembering the old woman's advice, throws it away secretly and begins to snore very loudly as if asleep.
The princesses, sure that the soldier is asleep, dress themselves in fine clothes and escape from their room by a trap door in the floor. The soldier, seeing this, dons his invisibility cloak and follows them. He steps on the gown of the youngest princess, whose cry of alarm to her sisters is rebuffed by the eldest. The passageway leads them to three groves of trees; the first having leaves of silver, the second of gold, and the third of diamonds. The soldier, wishing for a token, breaks off a twig of each as evidence. They walk on until they come upon a great lake. Twelve boats with twelve princes are waiting. Each princess gets into one, and the soldier steps into the same boat as the youngest. The young prince in the boat rows slowly, unaware that the soldier is causing the boat to be heavy. The youngest princess complains that the prince is not rowing fast enough, not knowing the soldier is in the boat. On the other side of the lake stands a castle, into which all the princesses go and dance the night away.
The princesses dance until their shoes are worn through and they are obliged to leave. This strange adventure continues on the second and third nights, and everything happens just as before, except that on the third night the soldier carries away a golden cup as a token of where he has been. When it comes time for him to declare the princesses' secret, he goes before the king with the three branches and the golden cup, and tells the king all he has seen. The princesses know that there is no use in denying the truth, and confess. The soldier chooses the eldest princess as his bride for he is not a very young man, and is made the king's heir.