A character arc is the internal journey of a character that happens over the course of the story. The character starts the story one way and ends the story another way. Simply put, it is the character’s personal transformation that happens because of events in the story.
Usually it is the protagonists or main character of a story that experiences an arc but supporting characters and even the antagonist can experience an arc as well. Often the character arc focuses on a personality trait. (Jill learns to forgive herself). In the beginning she is not able to forgive herself for something that happened in the past and by the end of the story she is able to forgive herself. (Eric stops being greedy). In the beginning of the story, Eric is greedy and because of experiences he has during the story, he becomes giving.
The character arc plays out over the three-act structure. During act one, the character arc is established by showing the character’s traits that will change. During act two, those character traits are challenged, and the character is forced to grow. Then during act three, those traits are fully changed, and the character has a new sense of self.
Famous Character Arcs:
Tony Stark (Iron Man): Tony Stark starts the story as a selfish, arrogant man-child. He concludes the story as a selfless hero.
Daenerys Targaryen (A Song of Ice and Fire) (Game of Thrones): Daenerys starts as a meek and naïve child. She concludes the story as a powerful conqueror – although she does fall from grace.
Michael (The Good Place): Michael starts as an evil demon torturing the main characters of the show and ends the story as a good human and a supporting savior of humanity.
Shadow Moon (American Gods): Shadow starts the story as a man who feels he is without meaning and ends the story with a renewed sense of self-worth and purpose.
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Let me know what characters you thought had the strongest character arcs and why. Personally, one of my favorites is Tony Stark’s over the course of the entire MCU because he shows how drastically one person can change and the impact that change can have on the world around them.