Part 2/7:
Scott Lang has moved on from his superhero days post the epic battle against Thanos. Embracing a more grounded life, he pens a biography detailing his adventures, catapulting him and his family into the limelight in San Francisco. However, during a book promotion event where he reads his story to children, a phone call alerts him to trouble involving his daughter, Cassie, who has been arrested for using Pym particles to shrink a car.
After rescuing her, Scott returns home to find Cassie, alongside his wife Hope and father-in-law Hank Pym, immersed in research about the Quantum Realm. Their excitement quickly turns to chaos when Cassie activates a device that inadvertently opens a portal to the Quantum Realm, resulting in the entire family being sucked in along with a group of ants.