Elodie apprentices with a dragon as a spy/detective-in-the-making and unravels the plot of an evil Princess who tries to assassinate both her father the King and a kindly Ogre Lord. Elodie is a young girl who wants to be an apprentice “mansioner” or actor. She travels to the city of Two Castles which is the capital of the kingdom of Lepai. There, she plans on attending Guild Week, which is a week where masters from across the kingdom arrive in Two Castles to find an apprentice. If she succeeds in getting an apprenticeship, she will be gone from home for ten years. She didn't tell her parents the truth about why she wanted to go to Lepai - they think she's going to do something more practical like apprentice as a weaver. Elodie plans on proving to them how great it is to be an actress when she succeeds as a mansioner in Lepai.
On the boat trip to Two Castles, she learns from a woman that there is an ogre in Lepai who is a Count called Jonty Um as well as a dragon in Two Castles. Before she leaves, the woman insists to gift Elodie with a cat. She explains that ogres can shape-shift and when a cat stares an ogre in the eye, it will transform into a mouse. When she arrives in Two Castles, she sees that many young children spend their days training cats for this reason. To her dismay, the cat the woman gave her steals her coin pouch and runs off with it. Elodie realizes she has been tricked and must now wander the streets begging. She is very disappointed as in order to become an apprentice, she will have to pay an apprenticeship fee. In the marketplace, she sees the unusual dragon of Two Castles roasting meat on skewers to sell to people for coin. The dragon, named Meenore, advises Elodie to apprentice a man named Sulow and offer a longer but free apprenticeship as a mansioner. Elodie follows the advice but she is still rejected as Sulow has already taken more than enough apprentices.
Later on, Meenore asks Elodie whether she would instead like to be her assistant. She will pay her and maybe eventually, Elodie can earn enough money to pay for an apprenticeship. Meenore turns out to be a creature of reason and logic and begins to train Elodie to become a "masteress" of deduction. One of the tasks Elodie is asked to do is read to her from the books she collects. Meenore also asks Elodie to peddle her skills at the marketplace – telling everyone that Meenore can find lost things and solve riddles. Elodie attracts the attention of Count Jonty Um, who wants the dragon to find his beloved dog. Meenore thinks the Count is in more danger than he realizes. The Count admits that the locals have been hostile towards him because he is an ogre and someone is poaching from him. Meenore asks Elodie to go and live with the Count and observe everything closely to try to gather clues as to who might be the culprit.
While investigating, Elodie witnesses the Count transform into all sorts of animals, something he doesn't simply show to anyone as it is a painful process. Elodie wonders if this is a sign that he trusts her. When she is at Count Jonty Um's castle, she meets the Princess Renn, who has been betrothed to the ogre. The Princess is eager to help Elodie find the Count's missing dog, as she feels like this will be a sure way to impress him. Apparently, she really likes the Count because he seems to have an affinity with animals and she loves animals. They investigate the castle stables but only find Master Thiel, a handsome young man, asleep in one of the stalls.
Elodie visits Meenore to report what she has learned. The dragon thinks the people of Two Castles will not like the idea of the Princess marrying an ogre, no matter how kindly Count Jonty Um is as this will mean they will be ruled by an ogre. She also tells Meenore about finding Master Thiel. Meenore tells Elodie that Master Thiel plans on marrying into wealth as his family is severely destitute due to his father's bad gambling habits. She orders Elodie to never let the Count of her sight and to keep an eye out for Master Thiel and any antics he might be up to.
One day, Elodie is running by the castle walls when she sees a dog that fits the description of Nesspa, the Count's missing dog. She returns Nesspa to the Count who is immensely grateful. The Princess is a bit disappointed, though, as she was hoping to be the one to return the dog. Later on, Elodie catches a cat that belongs to Master Thiel. The cat has stolen a pouch of coins from Master Thiel's brother, and the brother is not amused. Over the next few days, Elodie also learns how to be a cupbearer for Count Jonty Um, Princess Renn and the king. She undergoes a humiliating ordeal the first time she has to pour wine for the king, as the King seems to enjoy humiliating others. At the dinner that night, the King makes an announcement that Princess Renn will marry Count Jonty Um and lead the King's army. When the Count stands up to make a speech, however, no one shows him the respect of his rank and he sits down, humiliated. That night, Elodie performs in her first act as a mansioneur and impresses the nobles.
The show is interrupted by a gang of cats led by Master Thiel's cat. The presence of all the cats makes Jonty Um transform into a mouse and he disappears and chaos ensues. Later that night, Elodie overhears a few people discussing who they think is responsible for letting the cats loose in the palace. They think that the King might be involved, as he has always wanted to control the Count's castle. They also think Master Thiel could be involved because his cat was among the gang that chased off Jonty Um. Everyone hopes Jonty Um is alive as they are afraid that the King will be a harsh master. Later that week, there is news that the King plans on getting his daughter betrothed to another wealthy earl.
Meanwhile, Elodie is taken as an apprentice by Sulow because she has shown she has great skill. Meenore will not let her go, however, until she has solved the mystery of Count Jonty Um's disappearance and who is responsible for harassing him and his animals. One night, Meenore accompanies Elodie into the forests surrounding the Count's castle. They catch Master Thiel poaching. They accuse him or orchestrating the transformation of the Count into a mouse but Thiel insists he is innocent. He tells him he thinks it's the Count's friend, Sir Misyur, who is responsible as the man inherits everything if the Count is dead. The dragon and Elodie think Thiel is lying as he stands to gain if the courts think Sir Misyur and repossess the land. The repossessed land can then easily be given to either the King or him. Master Thiel tells him this is not possible since the King has apparently been poisoned the night of the Count's disappearance. Elodie is shocked at how cold Thiel can be about this news.
Elodie ends up being arrested for being suspected of poisoning the King, since she was his official cupbearer. While in prison, Elodie is visited by Princess Renn. The Princess offers her a meal of lamb stew. Elodie becomes suspicious that the Princess poisoned it since she seems very insistent that she eat it and keeps claiming that she had the same meal. Elodie tries to get Meenore to help her escape but the dragon is shot by an arrow and is severely injured. Elodie decides to use her talents as a mansioneur to trick the guards into setting her free down by acting in her play.
After escaping, she rushes to see the King, using her imitation of the Princess' voice to gain entry into his chambers. She tells the King all she knows and the King asks to see his daughter. They discover the Princess keeps the poison in her shoe and an antidote for the poison is brought to the King. Elodie is allowed to go and she rushes back to Meenore. She is relieved to find that the dragon's wounds have been taken care of. To her great delight, she also finds Count Jonty Um who had also been poisoned by the food the night of his disappearance. He explains that he's been in hiding since, but he will be glad to return home. The story ends with Elodie deciding she doesn't want to be a mansioneur after all as she prefers working for Meenore, solving mysteries.
Best part of story, including ending:
I like that the culprit who has been poisoning everyone was actually Princess Renn because she was such an overly happy and annoyingly giddy person that no one would have thought she was capable or even intelligent enough to do what she did. It was a surprising twist that was built up nicely through the story.
Best scene in story:
My favorite scene was when Elodie tries to escape from her prison. She uses her voice-imitation skills to pretend she is the princess and escapes via a trapdoor to elude the soldiers. It was a very amusing scene and quite thrilling because the real Princess was nearby and could have caught her.
Opinion about the main character:
I like that Elodie is clever and figured out that the Princess was trying to poison everyone based on subtle things the Princess reveals. I also like that Elodie is open-minded, as she is able to befriend both a dragon and an ogre, creatures that are essentially outcasts in society.