The story of Ant-Man and the Wasp: Quantumania reveals the real reason for Kathryn Newton taking on the role of Cassie Lang, previously played by Emma Fuhrmann in Avengers: Endgame. Fuhrmann replaced Abby Ryder Fortson, who had played the daughter of Scott Lang (Paul Rudd) in his first two cinematic outings as Ant-Man. The character was recast in Endgame due to the 5-year blip caused by Thanos' snap in order to better reflect the time-jump between Ant-Man and the Wasp and Endgame. Cassie Lang has been recast once more for Ant-Man 3, and the plot details reveal a good story reason for this decision.

The latest Ant-Man 3 trailer reveals further details of Scott Lang's relationship with Kang the Conqueror (Jonathan Majors). Finding themselves trapped in the Quantum Realm, Scott, Cassie, and the van Dyne family are thrust into an adventure far different from the buddy comedy heist movies of the previous two Ant-Man movies. While there, Scott is seen to make a Faustian Pact with Kang, which could doom both him and the wider MCU in order to get more time with his daughter Cassie. It's this motive for Scott's pact with Kang that explains the reason for Cassie's recast.

Related: Kang Already Risks Repeating Marvel's "Thanos Was Right" Problem

The REAL Reason Ant-Man 3 Recast Cassie Lang

Kathryn Newton as Cassie Lang in Ant-Man and the Wasp Quantumania and Emma Fuhrmann in Avengers Endgame

Having Kathryn Newton, rather than Emma Fuhrmann or an older Abby Ryder Fortson emphasizes Scott's unfamiliarity with his daughter. She's literally not the child he helped to raise in the previous films and is now someone else entirely. So determined is he to be a better father that Scott's desire to make up for lost time could lead to Kang killing Ant-Man. This tragic ending would complete Scott's redemptive arc as an absent father, acknowledging that he wasn't there and that he can't change the past but can sacrifice himself to protect his daughter's future.

From what's revealed in the Ant-Man 3 trailer, it appears Cassie is following a very similar path to her father Scott, prior to him becoming both Ant-Man and an Avenger. One scene finds her being released from a jail cell, suggesting that she, like her father before her, has gone off the rails into a life of crime. It's likely that Scott will blame himself for Cassie's fall from grace, given that he spent the five years of The Blip trapped in the Quantum Realm, unable to see his daughter or change the path she's on. This is key to Ant-Man's deal with Kang; he wants to turn back time and be there for his daughter.

Why Cassie Lang Can Replace Ant-Man In The MCU

Kathryn Newton as Cassie Lang in Ant-Man and the Wasp Quantumania and Emma Fuhrmann in Avengers Endgame

Another reason for casting Kathryn Newton as Cassie Lang is that she's a known star who could potentially continue the Ant-Man legacy. In the comics, Cassie Lang was determined to become a hero like her father by secretly exposing herself to the Pym Particles that are key to Ant-Man's size-altering powers. From Kathryn Newton's purple costume in the Ant-Man 3 trailer, it reveals that at some point in the movie, Cassie will assume her Stinger alter-ego from the comics.

As Stinger, Cassie has similar powers to Ant-Man and the Wasp, and she joined the Young Avengers following the death of her father. With Ant-Man and the Wasp: Quantumania turning Scott's daughter into a superhero, it continues an MCU trend of setting up its next generation. Ms. Marvel (Iman Vellani) idolized Captain Marvel (Brie Larson), and Kate Bishop (Hailee Steinfeld) idolized Hawkeye (Jeremy Renner), so it would make perfect sense for Cassie Lang to follow in the footsteps of her father Scott in the MCU's future.

More: Will Ant-Man Die In Quantumania? Marvel REALLY Wants You To Think So

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