Illustration by H. J. Ford
"The Troll's Daughter" is a Danish fairy tale collected first by Svend Grundtvig and then by Andrew Lang.
A young man going to seek his fortune agrees to serve a troll for three years, which involves a bizarre mixture of feeding an impossible number of animals and being morphed into various creatures.
During one of these transformations, he finds and falls in love with the troll's beautiful daughter.
However, the troll does not want a son-in-law, and the young couple must defeat several obstacles to live happily ever after.
This tale includes examples of the following tropes:
- Forced Transformation: The troll turns his servant into three different creatures (a hare, a bird, and a fish) after giving him permission to take a break for a while. The transformed boy spends a lot of time running because the troll has enchanted and caged up all the rest of the creatures. However, the third transformation backfires on him when the boy-turned-fish ends up finding and falling in love with the troll's daughter.
- Gilded Cage: The castle where the troll hides his daughter is made of glass with lovely furnishings and fascinating undersea sights. She wears colorful silk and always has more than enough food. However, she can't leave or have visitors. Tired of it, she comes up with a plan for the young man to help free her.
- I Gave My Word: Once the boy's term of service is up, the troll asks if he wants to serve for another year for another large amount of money. The boy says no, and the troll has to let him go by the terms of the agreement.
- Impossible Task: Being the villain of the tale, the troll naturally demands a lot of impossible things from his servant.
- His "service" includes being forced to feed a stable of starving animals in a single day. The stable varies from a mile long to three miles long. Somehow the boy still manages to do it.
- After the "jester" (the young man in disguise) causes a lot of damage, the troll demands that the king repay him by answering four questions which no one besides him and his daughter could possibly know. The young man, who spent much of the year courting the troll's daughter, answers them all correctly.
- Mad Scientist's Beautiful Daughter: The troll has a lovely daughter who he keeps in an undersea castle to keep anyone from taking her away. She has grown tired of it and plots with the hero to gain her freedom.
- Needle in a Stack of Needles: The troll insists that the hero pick his daughter and the fish that holds his heart out of a myriad of identical duplicates. The young woman helps both times by giving her suitor a clue.
- Off with His Head!: The troll's daughter warns her suitor to be ready when her father calls his fish-self back, because if her father caught him at the castle, he would cut his head off.
- On One Condition: The troll's daughter advises the hero to enter the service of a king who owes her father money. When the debt is almost due, he is to offer to lend his master the sum on the condition that he goes on the visit dressed as a jester and does anything he wants. Having no recourse, the king is happy to agree.
- Patricide: The troll's daughter helps her young suitor kill him.
- Words Do Not Make The Magic: Inverted; The troll changes his servant's form three times with a special poem. Upon seeing the troll's daughter, the boy-turned-fish remembers it and turns himself back so he can visit with her.
