Every Character Not Returning In The Matrix 4

[The Orgazoid]

Rumors and fan theories as to what The Matrix 4 will entail fall into two categories: that it will be a passing of the torch ushering in a new generation of characters, and even a new trilogy, or that it could be a time-travel story, since Neo and Trinity are slated to return despite their deaths in The Matrix Revolutions. The latter theory opens the door to some beloved characters potentially returning as younger versions of themselves and played by different actors: Yahya Abdul-Mateen II, Neil Patrick Harris, Priyanka Chopra, Jessica Henwick, Jonathan Groff, Toby Onwumere, Max Riemelt, Eréndira Ibarra, Andrew Caldwell, Brian J. Smith, and Ellen Hollman have all been cast in so-far undisclosed roles. Therefore, while a number of characters from the original trilogy will not be returning in The Matrix 4, some of them could still show up as younger versions of themselves and be played by different actors despite not having their appearances confirmed.
The Oracle
The Matrix Oracle Recast

The Oracle was a pivotal figure in all three of The Matrix movies. While narratively her main function was prophesizing the coming of “The One,” she was also revealed to be a sapient program integral to the very nature and existence of the Matrix itself. It’s difficult to imagine how The Matrix 4 could unfold without The Oracle’s presence as one of the two balancing forces of the Matrix; she represents the fallible human factor of the program. Considering actress Mary Alice took over from the  original actress Gloria Foster in The Matrix Revolutions, precedent has already been established for The Oracle to manifest in a new form, and it would therefore be just as easy to recast her in the fourth installment.
Seraph

If The Oracle returns, the likelihood is that her loyal bodyguard Seraph would as well; when last seen in The Matrix Revolutions, Seraph was well and alive. Played by Collin Chou in the two sequels, Seraph behaves as gateway to accessing The Oracle and anyone who wishes to speak with her must prove their credentials – their fighting prowess – before being permitted access. It is also possible that The Oracle would seek a new guardian in The Matrix 4, depending on which timeline the film adopts.
The Architect
The Architect from The Matrix Reloaded

Already mentioned is The Oracle, one of the two opposing forces of the Matrix. The other is The Architect, the creator of the Matrix and representative of the cold logic of machines, acting as the system’s chief administrator. It also follows that The Architect could not return without The Oracle, and vice versa, given their Yin and Yang balancing of the power structure and the fact that The Matrix franchise can be interpreted as a battle between free will (The Oracle) and determinism (The Architect). If The Matrix 4 were to leave these characters behind, it would need to find an entirely new philosophy upon which to base itself. It is much more likely that audiences will see The Architect return in some form, though he will not be characterized by Helmut Bakaitis.

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How The Matrix 4 Can Re-define Sci-Fi Movies (Again)
Morpheus

Arguably as key a figure as Neo (Reeves) and Trinity (Moss) in the original trilogy, Laurence Fishburne nevertheless has not been confirmed to return in The Matrix 4; however there have been rumors of his character’s return, potentially as a younger version of himself. A Zion operative and widely respected spiritual figure to the city’s citizens, Morpheus had a crucial role in the original The Matrix trilogy as a freedom fighter, a believer in the Prophecy, and a mentor to Neo. If a younger version of Morpheus turned out to be reality, Yahya Abdul-Mateen II would be the obvious casting choice.
Sati

While the young girl began life as an exiled program, The Oracle would soon take Sati (Tanveer K. Atwal) under her wing, believing her to have an important role in the future of the Matrix. Her role remained cryptic in The Matrix movies but was emphasised as one of great importance, so Sati’s potential role in The Matrix 4 is full of opportunities. Likewise, Sati’s return would also be entangled with the returns of The Oracle, Seraph, and The Architect. In addition, if The Matrix 4 intends to launch a "next generation" The Matrix trilogy, Sati could serve as a connection between it and the original movies and could believably be played as an adult by Priyanka Chopra.
Ghost

Since Jada Pinkett Smith has been confirmed to return as Niobe, it would make sense for Anthony Wong to also return as Ghost, despite his return not having been announced. Ghost was the First Mate and gunner of the Logos, one of only three crewmembers who also included Captain Niobe and Operator Sparks. He also had a close relationship with Trinity, another character returning in The Matrix 4.
Persephone

With Lambert Wilson confirmed to return as The Merovingian in The Matrix 4, it would come as no surprise if his wife Persephone, played by Monica Bellucci, also made an appearance. Though their marriage is an unhappy one and Persephone previously betrayed her husband to help the Resistance, they were still seen together in Club Hel after she had helped Neo, suggesting their marriage endured the betrayal. Duology is also a key motif of The Matrix films, with many characters being paired in relationships as a way to maintain balance. It would therefore be odd for The Merovingian to return solo in The Matrix 4, though perhaps he will simply find another partner.