SPOILERS for Agents of S.H.I.E.L.D. "The Devil Complex" ahead

"The Devil Complex" saw Agents of S.H.I.E.L.D. take another remarkable twist, revealing that Fitz is not the man he was. One of the show's longest-running heroes is now as much foe as he is friend; a dark corner of Fitz's psyche has been unlocked, releasing the sinister version the show is referring to as "Leopold." This version aligns with the character introduced in the Framework, a mastermind who's far more ruthless than the Fitz fans know and love.

For Jemma Simmons, this is the most heartbreaking twist to date. The newlyweds won't be allowed a honeyman period, and sadly Fitz really is no longer the man she married. He's something far worse, his psyche torn apart, his mind split into two personalities who are at war with one another. It's yet another obstacle for the S.H.I.E.L.D. team to add to their list, an already formidable one that includes "the Earth's imminent destruction," "General Hale," and "dimensional rift unleashing our worst fears." (Though, as of this episode, that last obstacle seems to have been dealt with.)

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Ironically, though, this so-called "psychic split" may actually be just what the team needs. Already, Leopold has successfully unlocked Daisy's powers in order to save the world from the threat of the fear dimension. Could the Framework's version of Fitz actually save the world?

THIS PAGE: JUST WHAT'S HAPPENED TO FITZ?

Fitz's Psychic Split in 'The Devil Complex' Explained

Agents of S.H.I.E.L.D. Season 4 saw Coulson and his team trapped in an immersive virtual reality, one where their greatest regrets had been written out of history. The Framework swiftly turned into a nightmare world, one ruled by Hydra. The S.H.I.E.L.D. team lived different lives. Coulson, for example, was a history teacher. In the Framework reality, Fitz had remained under his father's wing. This had led him to grow up into a very different person, becoming a confident figure who rose through the ranks of Hydra. Fitz ultimately became Madame Hydra's second-in-command - and Ophelia's lover. Unrestricted by petty morality, the Framework version of Fitz unlocked whole new avenues of science and technology. He was also willing to torture and kill without a qualm, and murdered Holden Radcliffe's lover.

When the S.H.I.E.L.D. team were brought out of the Framework, they were left reeling, struggling to deal with their return to reality. Each member of the team had two sets of memories. For most, the alternate memories seem to have diminished over time. But Fitz's were dramatic and disturbing, not least because he knew he really had been responsible for killing a real person who was trapped within the Framework. Poor Fitz's grasp on reality was only made worse when he was spirited away by Ophelia.

It's important to remember that Fitz is actually the most vulnerable of the S.H.I.E.L.D. team. Way back in Season 1, Fitz suffered severe brain damage due to oxygen deprivation. That actually led Fitz to hallucinate in Season 2, to imagine Jemma alongside him. Brain damage like that doesn't just go away; Fitz was always going to be the most vulnerable after emerging from the Framework. Making matters worse, both versions of Fitz are scientists, meaning large tracts of their knowledge intersect. Every time Fitz approaches a scientific issue, he's potentially tapping into the part of his brain that was shaped by the Framework. He also tapped into the ruthlessness of his Framework version while trying to bluff his way into Kasius's favor on the Lighthouse, establishing a further link to the Framework memories and persona.

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The ultimate consequence, then, is that Fitz's mind has fragmented. He appears to now be suffering from a form of Dissociative Identity Disorder, with the trauma of the Framework creating two separate personalities. The "Leopold" identity embodies the life he lived in the Framework, and could easily become a terrifying opponent for S.H.I.E.L.D..

Can Fitz Be Saved?

Ironically, the show's time-travel concept has already dropped heavy hints that S.H.I.E.L.D. will be able to treat Fitz's condition. "The Last Day" included a series of flashbacks (flashforwards?) that revealed the future timeline. They included glimpses of Fitz, clearly in his right mind, and still married to Jemma. In one scene, he was horrified and furious when Robin foretold Simmons's death.

But those were only brief scenes, and they're not really enough to say for sure that Fitz will be okay. The reality is that treatment of DID typically focuses on unifying the personalities, not on destroying one of them (as S.H.I.E.L.D. want to do). The "Leopold" personality has been absorbed into Fitz's brain, and is now a part of him. Fitz will have to accept this disturbing new identity, and acknowledge that he is no longer the man he was. Only then, possibly with years of treatment, can Fitz find a measure of stability. Meanwhile, it's also worth noting that the flashback scenes clearly showed an angry, irritable version of Fitz who had no time for prophetic children. That certainly tallies with the post-Framework Fitz, his mind damaged by his experience of another life.

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Of course, Agents of S.H.I.E.L.D. is as much a science fiction series as a superhero show, and S.H.I.E.L.D. already have technology that can manipulate the memories. Season 1 introduced a Hydra memory-machine, one that allowed Coulson to revisit a past that had been carefully wiped from his memories. By Season 2, S.H.I.E.L.D. had developed enough understanding of the tech to overwrite Calvin Zabo's memories, creating a fake identity for Daisy's father. It's possible that memory-machine could be Fitz's salvation, allowing the S.H.I.E.L.D. team to erase the memories associated with Leopold. As "Principia" reminded viewers, though, a mistake with that technology can cause problems all of its own. It seems unlikely to be a coincidence that the show reminded viewers of this tech right before revealing the psychic split.

What Leopold Means For Agents of S.H.I.E.L.D.

Disturbingly, though, it may well be better for the world if S.H.I.E.L.D. were to fail. The team are desperate to avert a dystopian future in which the Earth had been shattered, and the key is surely to find potential places where the timeline can diverge. So far, Coulson and his team are on track for the Earth's destruction. Every detail is seeming to align perfectly. But Fitz's shattered psyche adds another variable. If S.H.I.E.L.D. are unable to blend Fitz's personalities, or if the Leopold personality becomes dominant, then the timeline is subtly changed.

As "The Devil Complex" reveals, Leopold doesn't want the Earth to be destroyed any more than S.H.I.E.L.D. do. He's simply willing to take more ruthless steps to prevent it. What's more, it's entirely possible Leopold has a depth of scientific knowledge that our Fitz doesn't. In the Framework reality, after all, Leopold was able to synthesize Terrigen - a feat the real Fitz wouldn't be able to accomplish. Leopold's scientific knowledge may actually be of tremendous value to S.H.I.E.L.D., and it's currently unclear whether Fitz can access that knowledge.

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It's entirely possible that, in order to save the world, S.H.I.E.L.D. will need to allow a man they love to lose himself to his worst nightmare. Thematically, that concept fits perfectly with the second half of Season 5, which seems dedicated to the theme of fear itself.

Why Keeping Leopold Would Be Good For Agents of S.H.I.E.L.D.

Agents of S.H.I.E.L.D. has always celebrated the theme of family, and its best villains have always come from within. The ultimate example is Grant Ward, whose betrayal transformed a lackluster first season. Ward's ruthless evil became the central plot thread for the next two seasons. A betrayal like Fitz's, though, one in which the S.H.I.E.L.D. team were as desperate to rescue him as to defeat him? That's narrative gold, and the show's writers could mine it with ease. Particularly if, in another plot twist, Jemma is actually pregnant.

Meanwhile, it's worth stressing that Leopold is loyal to Hydra - and Hydra seems to be resurgent. General Hale has ties back to key Hydra figures like Baron Von Strucker, although she claims to want to build something different. Unknown to Hale, her own daughter Ruby has another agenda, and has seduced Werner Von Strucker into supporting it. The shadow of Hydra looms large over Agents of S.H.I.E.L.D. once again, and Leopold could easily become a leader within the reinvigorated organisation.

This is the kind of plot twist that S.H.I.E.L.D. has always excelled at, turning a character's life upside-down in an instant. The future of Agents of S.H.I.E.L.D. is currently uncertain - the showrunners are ready for its cancellation, but ABC President Channing Dungey is "cautiously optimistic" about the series's future. If S.H.I.E.L.D. is to stick around, the Leopold plot twist could easily become a central part of the next few seasons.

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Marvel's Agents of S.H.I.E.L.D. airs Fridays @ 9 pm on ABC.