Riley is born in a small town in Minnesota. Within her mind's Headquarters, five personifications of her basic emotions—Joy, Sadness, Fear, Disgust, and Anger—come to life and influence her ways of doing things via a control console. As she grows up, her experiences become memories, stored in colored orbs, which are sent into long-term memory each night. Her five most important "core memories" are housed in a hub; each powers an aspect of her personality which takes the form of floating islands. Joy acts as a de facto leader, and since she and the other emotions do not understand Sadness's purpose, she tries to keep Sadness away from the console.
