After being outlawed for years, superheroes continue to live their lives under secret identities, despite their desire to use their powers for the greater good. Bob Parr, his wife Helen, and their children Violet, Dash, and baby Jack-Jack face a new challenge when a wealthy entrepreneur, Winston Deavor, and his sister Evelyn propose a campaign to restore the public's faith in superheroes. They choose Helen, also known as Elastigirl, to be the face of their movement, forcing Bob, better known as Mr. Incredible, to stay at home and care for the children. This role reversal highlights the family dynamics as they grapple with normal life and Jack-Jack's emerging powers.

As Elastigirl embarks on her new mission, she encounters a new villain, Screenslaver, who uses hypnotism to control people through television screens. While Helen works to uncover the mysterious villain's identity and motive, Bob struggles with the trials of domestic life, including Violet's teenage troubles, Dash's homework, and the unpredictable array of Jack-Jack's abilities. Their efforts to adapt to their new roles while maintaining a united front as a family set the stage for both humor and conflict.