In Kang’s voiceover, he strikes a Faustian note as he says, “You’re an interesting man, Scott Lang. You’re an Avenger. You have a daughter, but you’ve lost a lot of time, like me. We could help each other with that.” As this is happening, we see the young Cassie Lang (Abby Ryder Fortson) wallpapered on Scott’s phone. Then, we see the full-grown Cassie (Kathryn Newton) walking out of a jail cell.
This would seem to imply that Cassie might have followed her father’s footsteps into a life of crime. Thanks to the events of “Avengers: Infinity War,” “Ant-Man and the Wasp,” and “Avengers: Endgame,” Scott was stuck in the Quantum Realm for five hours while five whole years elapsed on earth. He missed the chance to see his daughter grow up, and it’s possible that, in his absence, Cassie may have made some of the same mistakes Scott did before the first “Ant-Man” movie, where he was released from prison for petty thievery.
Whatever the case, the trailer picks up where the last one left off, with the activation of a device that Cassie described in the first trailer as “like a satellite for deep space, but quantum.” We see Hope and her mother, Janet van Dyne (Michelle Pfeiffer), looking on as it throws off a blue glow. Soon, pieces of furniture, then Cassie, then Scott — pretty much everything and everyone in the room — are getting sucked down into the Quantum Realm.