Inside Out

In the mind of a young girl named Riley Andersen are five personified emotions that influence her actions: Joy, Sadness, Fear, Disgust, and Anger. They process her experiences into memories stored as colored orbs in "Headquarters", her conscious mind, and send them into long-term memory each night. The aspects of the most important "core memories" within her personality take the form of five floating islands. Joy acts as the leader and tries to limit Sadness's influence, perceiving her as an unnecessary burden for Riley.
At age 11, Riley moves from Minnesota to San Francisco for her father's new job. On Riley's first day at her new school, Sadness retroactively saddens joyous memories, making Riley cry in front of her class. This creates Riley's first sad core memory. Joy tries to dispose of it using a pneumatic tube but knocks loose the other core memories during a struggle with Sadness, disabling the personality islands. Joy, Sadness, and the core memories are sucked out of Headquarters. In their absence, Anger, Fear, and Disgust attempt to create new happy core memories but push Riley away from her parents, friends, and favorite activities. Goofball, Friendship, and Hockey Island thus collapse into the Memory Dump, where forgotten things gradually disappear forever.
In the vast long-term memory area, Joy and Sadness encounter Bing Bong, Riley's childhood imaginary friend, who suggests riding the "train of thought" back to Headquarters. They miss it after Bing Bong naively leads them into Abstract Thought. In Imagination Land, which is under heavy renovations, Bing Bong bemoans Riley outgrowing him and rejects Joy's attempts to cheer him up in favor of Sadness's empathy. The trio catches the train, but it stops when Riley goes to sleep. At Dream Productions, Bing Bong is imprisoned in Subconscious for crashing a dream being filmed; Joy and Sadness get themselves arrested and free him as well as Jangles the Clown, Riley's scariest memory, frightening her awake. Meanwhile, Anger inserts an idea bulb into the console to make Riley run away to Minnesota, believing this will form new happy memories.
Honesty Island collapses after Riley steals her mother's credit card, leaving only Family Island and derailing the train. Joy tries to ride a "recall tube" back to Headquarters, but the ground below collapses, plunging her and Bing Bong into the Memory Dump. Joy discovers a sad memory of Riley losing an ice hockey game that turns happy when Riley's parents and friends comfort her. She realizes Sadness's purpose is to alert others when Riley is emotionally overwhelmed. Joy and Bing Bong try to use his song-fueled rocket wagon to escape the Memory Dump, but cannot ascend due to their combined weight. On the third attempt, Bing Bong jumps out of the wagon mid-ascent, fading away as Joy escapes to freedom.
Anger's idea bulb shorts out the console, putting Riley into depression as she boards a bus to Minnesota. Joy and Sadness reunite and return to Headquarters while Family Island nears collapse. Joy hands control of the console to Sadness, who removes the idea bulb, restarting the console and prompting Riley to get off the bus and rush home. Joy, realizing Riley had independently made up her mind about moving to San Francisco, allows Sadness to make the core memories sad. Riley bursts into tears, telling her parents she misses her old life; they comfort her and admit they also miss Minnesota. Sadness and Joy join hands on the console, creating a new core memory that is both happy and sad. A new Family Island forms, representing Riley's acceptance of her life in San Francisco.
One year later, 12-year-old Riley has adapted to her new home, made new friends, and acquired new hobbies. Inside Headquarters, Riley's emotions admire both her new and re-formed personality islands, powered by multicolored core memories that contain mixed emotions, and are given an expanded console allowing them to work as a team. Although they admit slight concern over a red alarm light marked "PUBERTY", they decide that it is not important at the moment.