Doon is one of the main characters of The City of Ember. He sees there are problems in Ember and wants to help solve the problem. He is studious and tries to learn as much as he can about things. He often visits the library for research.
At the beginning of the story Doon is the kind of character who loses his temper easily. He wants change immediately and has a hard time waiting for things to change. For example, he sees that there is something wrong with the electricity in Ember, but is frustrated because no one else seems interested in solving the problem. One way he grows mentally is in his ability to be patient.
A big lesson Doon learns throughout the story is that sometimes adults cannot be trusted. Sometimes the people in power will abuse their power and trust. In the beginning of the story Doon and his friend Lena believe that if they share the information they've found with the mayor, he will help them. However, he does not help them. Instead, Doon and Lena learn the mayor is part of what is wrong in Ember, and is putting his own desires ahead of the town's basic needs.
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