Warning! This post contains SPOILERS for X-Men '97, episode 5, "Fire Made Flesh"

Summary

• Mister Sinister returns in X-Men '97, adapting his key role in the origins of Cable and Madelyne Pryor while proving his potential for a live-action role in the MCU's future.
• Sinister's darkly unethical experiments, immortality, and unique powers make him a compelling and evil villain for the X-Men.
• The MCU could finally introduce Mister Sinister after Fox failed, offering the chance to portray him as a genuine threat to of the X-Men and mutantkind overall in the greater cinematic universe.

Thanks to X-Men '97, episode 3, the titular team of mutants faces a major clone crisis and several eldritch horrors. As such, it's all thanks to the manipulations of one of the X-Men's greatest villains: Mister Sinister.

Following his multiple appearances in the original X-Men animated series, Mister Sinister returns in X-Men '97 to carry out one of his most infamous schemes surrounding his obsession with Scott Summers' Cyclops and his wife Jean Grey. Seeking the genetic perfection of mutantkind, Sinister is a unique X-Men villain whose evil comes in the form of his immoral experimentation on mutants, utilizing disturbing methods and immortality to great effect as he works in the shadows to achieve his dark goals. To that end, X-Men '97 helps prove how good Mister Sinister would be on-screen in the MCU.

X-Men '97 Just Reminded Everyone How Great Mr Sinister Is

Nathaniel Essex Seeks To Create The Perfect Mutant Race

Originally living in Victorian London, Nathaniel Essex was a contemporary of Charles Darwin who became fascinated with evolution and evidence of what he believed were single-generation leaps within humanity via mutations (later known as X-genes). Refusing to let his work be bound by the limits of morality, Essex was eventually ousted by the Royal Academy due to his darkly unethical experiments. In the comics, Essex discovers En Sabah Nur's Apocalypse who grants him near-instant regeneration abilities, telepathy, and energy blasts. However, the two villains eventually become rivals with Sinister seeking to create a mutant capable of killing the First Mutant.

In the original X-Men animated series, Sinister's origins aren't as tied to Apocalypse (Sinister's power comes from a serum). Essek even worked for En Sabah Nur in the fourth season's finale when Apocalypse attempts to control time itself. However, Sinister may still be working to bring about Apocalypse's demise thanks to X-Men' 97 episode 3. Continuing his obsession with Cyclops and Jean, it's revealed that Sinister created and replaced the original Jean with a clone, complete with Jean's memories. As such, the Jean clone gives birth to Nathan, a child with immense genetic potential that Sinister had long been seeking.

While there are some differences, X-Men '97 episode 3 effectively mirrors the comics and the origins of Madelyne Pryor. However, it also shows just how great of a villain Mister Sinister is, especially after he kidnaps Cyclops and Jean's baby and infects him with a techno-organic virus in a bid to make him invulnerable (and perhaps stronger than Apocalypse). There's no line Mister Sinister is unwilling to cross in the name of genetic perfection and the advancement of mutantkind.

Mr Sinister Is X-Men: The Animated Series' Best Villain

A True Embodiment Of Evil

In the original X-Men animated series, Mister Sinister frequently appears to antagonize the team of mutant heroes. Beginning with the brainwashing of Morph in X-Men's first season and manipulating him into hating the X-Men for a long period, Mister Sinister would continue his efforts to sabotage the team as he sought to conduct experiments on Cyclops and Jean. He even interfered with their wedding and kidnapped them on their honeymoon as seen in X-Men's second season.

Rather than groups like the Friends of Humanity or Bolivar Trask's mutant-hunting robot Sentinels, Mister Sinister isn't a villain who's intolerant of mutants. Instead, his evil comes from a more classic strain of mad science as he seeks to create the perfect mutant race. To that end, Minster Sinister carries so much narrative potential as a genuine threat, both personally for mutants like Cyclops and Jean but also for mutantkind overall with Sinister looking to disrupt and accelerate the natural processes of evolution.

The MCU Can Finally Use Mr Sinister For The First Time

Will Sinister Finally Come To The Big Screen?

It's worth noting that Fox tried to make a live-action Sinister happen in their X-Men movie universe. Multiple references and even a post-credits scene were made, and actor John Hamm was even in talks to play Mister Sinister. Although it ultimately fell through due to Disney's purchase of 20th Century Fox, it does mean Mister Sinister could finally happen now that the X-Men are positioned to be introduced in the MCU. With any luck, the MCU's Mister Sinister will be just as compelling and evil as the animated version.

New episodes of X-Men '97 air every Wednesday on Disney+.

Key Release Dates

• Blade (2025)

  Release Date:

  2025-11-07
• Avengers: The Kang Dynasty

  Release Date:

  2026-05-01
• Avengers: Secret Wars

  Release Date:

  2027-05-07