Welcome back to Rewatching Smallville, my weekly dive into the iconic series that explores Clark Kent’s journey before becoming Superman. Whether you’re a long-time fan or new to the show, you’re invited to join in each Tuesday as I revisit episodes and share my thoughts and observations. Be sure to share your own memories and theories in the comments below!

After last week’s surprisingly grounded character study in “Lucy,” Smallville swings back toward the fantastical with “Onyx,” an episode that literalizes Lex Luthor’s internal moral struggle by splitting him into two distinct personalities. It’s the kind of high-concept premise that could easily have devolved into camp or gimmick, but thanks to Michael Rosenbaum’s spectacular dual performance, “Onyx” becomes a fascinating—if imperfectly executed—exploration of identity, destiny, and the question of whether we’re defined by our darkest impulses or our conscious choices.

Written by Steven S. DeKnight and directed by Terrence O’Hara, “Onyx” gives us something Season 4 desperately needed: an episode that focuses squarely on one of its core relationships. The Lex and Clark dynamic has been simmering all season, with Lex making incremental steps toward the villain he’ll eventually become while Clark desperately clings to the belief in his friend’s inherent goodness. By physically separating Lex’s light and dark sides, the episode forces both characters—and us as viewers—to confront an uncomfortable question: Is Alexander (evil Lex) a corruption of Lex’s true self, or is he the real Lex that “good Lex” has been suppressing all along?

Two Luthors, One Michael Rosenbaum

Let’s start with what unquestionably works about this episode: Michael Rosenbaum’s performance. From the moment we see the two versions of Lex interact, it’s clear that Rosenbaum isn’t just playing “good guy” and “bad guy” versions of the same character. He’s crafted two distinct personalities that feel like genuine halves of a whole person, each incomplete without the other.

“Good Lex”—or Lex, as he’s referred to in production materials though not on screen—carries himself with an almost naive openness. When he shows Clark around the LuthorCorp lab, explaining his agricultural experiments with genuine enthusiasm, Rosenbaum plays him as unburdened by the paranoia and calculation that usually defines Lex. This version is generous, agreeing to his father’s charity fundraiser without the usual power plays or conditions. He’s the Lex who could have been, the one who might have emerged if Lionel had been a different kind of father.

But it’s in his portrayal of “Evil Lex”—Alexander—that Rosenbaum truly shines. This isn’t a mustache-twirling villain; this is someone who’s dropped all pretense of morality and discovered a kind of terrible freedom in that abandonment. The way Alexander moves is different—more predatory, more confident. His smile carries genuine menace rather than Lex’s usual charm-as-weapon. When he murders Dr. Sinclair by injecting air into his IV, Rosenbaum plays it with chilling casualness, like he’s checking off an item on a to-do list rather than ending a human life.

The scene where Alexander tells Chloe that the doctor is “sleeping now” and she should “come back later when he’s feeling a little more alive” is deliciously sinister. That dark wordplay, delivered with just the right amount of smug satisfaction, reminds us why Rosenbaum remains my favorite live-action Lex Luthor portrayal of all time. He understands that the most effective villains aren’t the ones who monologue about evil—they’re the ones who find genuine pleasure in their own cleverness, even when that cleverness serves terrible ends.

The Philosophy of Split Personalities

The episode’s central conceit—that black kryptonite can separate a person into their good and evil halves—is pure comic book science, and the show doesn’t waste time trying to justify it beyond “mysterious alien mineral does mysterious alien things.” But what makes “Onyx” more than just a gimmick episode is how it uses this split to explore genuine questions about Lex’s character and destiny.

Alexander’s conviction that he represents Lex’s “true nature” is compelling precisely because we’ve seen enough of Lex’s darker impulses to find it plausible. When he tells good Lex, “All the times you’ve meddled in his plans, derailed his ambitions. He’s thought about killing all of you—he just never had the guts to go through with it,” we know he’s not entirely wrong. We’ve watched Lex calculate and scheme, watched him prioritize power over people, watched him make choices that inch him closer to the villain he’ll become.

But here’s where the episode both succeeds and stumbles in its philosophical exploration. By making Alexander so cartoonishly evil—murdering people, shooting Jonathan, imprisoning his better half with an iron mask—the show oversimplifies Lex’s moral complexity. The real tragedy of Lex Luthor isn’t that he has an “evil side” that will inevitably dominate. It’s that he’s a man of genuine brilliance and potential for good who will, through a series of conscious choices driven by fear, ambition, and wounded pride, transform himself into the world’s greatest villain.

At this point in his story, Lex stands on the edge of the knife. He still has the potential to choose differently, to become someone other than his father’s son. The episode’s ending—with Lex’s cryptic smile after Lionel declares “We’re Luthors… we’re Luthors”—suggests that the die may already be cast, that perhaps Alexander was right about what lurks in Lex’s heart. But I don’t think this is where the real turn begins. That’s still to come, still contingent on choices Lex hasn’t yet made.

The Kryptonite Ring and Foreshadowing

One of “Onyx’s” most effective elements is how it previews the eventual Superman/Lex Luthor dynamic we all know is coming. When Alexander confronts Clark in the barn with his kryptonite ring, offering him a partnership where they could “rule the world together” as “gods among men,” it’s a chilling preview of their future relationship. The fact that Alexander already knows Clark’s secret—another inadvertent reveal that will be conveniently forgotten by episode’s end—allows the show to dramatize their fundamental incompatibility in stark terms.

Clark’s immediate rejection of Alexander’s offer, even before the kryptonite weakens him, tells us everything about why these two are destined to become enemies. Clark doesn’t want to rule or dominate; he wants to help and protect. The very thing Alexander sees as their greatest potential—the power to stand above humanity as gods—is anathema to everything Clark believes. Even when Alexander has him at his mercy, kryptonite draining his strength, Clark’s response is to appeal to the goodness he believes still exists somewhere in his friend.

The kryptonite ring itself is a nice touch, calling forward to the comics where Lex famously wears one (eventually losing his hand to kryptonite poisoning as a result). Alexander’s line—”I want you to remember this day, Clark. I want you to remember that, despite all your amazing powers, there was one man that beat you”—directly echoes Batman’s famous monologue from Frank Miller’s The Dark Knight Returns graphic novel, where Batman tells Superman, “I want you to remember, Clark, in all the years to come, in your most private moments, I want you to remember my hand at your throat. I want you to remember the one man who beat you.” It’s the kind of comic book Easter egg that rewards longtime fans without derailing the episode for casual viewers.

The Lionel Problem

The episode’s B-plot focuses on Alexander’s attempt to reawaken Lionel’s villainous nature, and honestly, I’m still not entirely sure how I feel about where the show has taken Lionel this season. The fencing scene between Alexander and Lionel is well-choreographed and tense, with Alexander taunting his father into reverting to his old self. When Lionel finally gives in and overpowers Alexander, you can see the satisfaction in both characters—Alexander happy to have his “real” father back, Lionel perhaps relieved to stop pretending to be something he’s not.

But here’s my read on Lionel at this point: I think his redemption has been genuine, a lingering effect of Clark’s pure soul temporarily inhabiting his body. John Glover has played Lionel’s struggle between his old and new selves with remarkable nuance all season, and his reversion here feels less like a revelation of his “true nature” and more like a man under extreme pressure falling back on familiar patterns.

The final scene between father and son—with Lionel announcing he’ll close the charity foundation and declaring “A man can’t deny his true nature. We’re Luthors”—works as a dark mirror to the episode’s central theme. If Alexander represents the idea that evil is Lex’s essential nature, Lionel’s words suggest that being a Luthor means that evil is hereditary, inescapable. Lex’s smile in response is perfectly ambiguous—is it satisfaction at having his father back, or recognition of a trap he’s walking into willingly?

Clark Kent: Professional Optimist

Clark’s role in this episode is quintessentially him—trusting, compassionate, and perhaps willfully naive about the darkness lurking in people he cares about. When he encounters “good Lex” at the hospital and later at the lab, he has no reason to suspect anything is wrong. Lex seems… well, like the best version of himself. Enthusiastic about his agricultural projects, unconcerned with power plays, genuinely friendly without calculation.

Tom Welling plays Clark’s growing concern beautifully as evidence mounts that something is very wrong. His confusion when confronted by Alexander—”No, you’re not him. The real Lex would never try to kill me or Chloe”—reveals Clark’s fundamental belief in his friend’s goodness. Even faced with a version of Lex who has dropped all moral pretense, Clark insists that this isn’t the “real” Lex, that the friend he knows would never go this far.

Of course Clark is too trusting. Of course he accepts good Lex’s amnesia about Alexander’s actions without question, assuring him that “the other Lex wasn’t actually you.” That’s who Clark Kent is—someone who believes in people’s better angels even when all evidence points to their worse demons. For Clark, that unwavering faith in others IS appropriate compassion. It’s also setting him up for heartbreak when Lex eventually becomes the enemy Clark refuses to see coming.

The barn confrontation, where Alexander offers Clark partnership in world domination, echoes the Warrior Angel and Devilicus dynamic the show has referenced before. Alexander’s revelation that he knows Clark’s secret—discovered by overhearing Clark’s excuse about the rotten apple making him nauseous near the kryptonite samples—should be a game-changing moment. Instead, it’s just another entry in the increasingly tired parade of “people discover Clark’s abilities and then conveniently forget them by episode’s end.”

The Forgetting Problem

Look, I need to address this directly: the amnesia thing is getting old. When it happened with Bob Rickman in “Hug,” it was a clever solution that made sense within the episode’s logic. When it happened with Morgan Edge in “Shattered,” it felt like a narrative cheat but at least involved dramatic electroshock therapy. But this is now the fourth time Lex has discovered Clark’s secret (if we count “Dream Lex” in “Slumber”), and the fourth time he’s conveniently forgotten it before the credits roll.

I understand why the writers do this. The show needs Lex to remain in the dark about Clark’s abilities for the friendship to continue, for the slow-burn tragedy of their relationship to maintain its tension. If Lex knew for certain that Clark had powers, everything would change immediately. The entire dynamic would shift in ways the show isn’t ready to explore in Season 4.

But understanding the narrative necessity doesn’t make it less frustrating. The resolution here—that Lex doesn’t retain any of Alexander’s memories—is just too convenient. It’s a cop-out that treats memory as a plot device to be toggled on and off rather than as an integral part of character. And the fact that this same trick is going to be used again with Lex only makes it more tired.

Manufactured Drama and Inappropriate Seeds

Let’s talk about Alexander kissing Lana and threatening to close the Talon unless she moves in with him. On one level, it makes sense for Alexander—the version of Lex without moral restraints—to act on impulses that good Lex would suppress. He wants Lana, so he kisses her. She rejects him, so he leverages his financial power over her. It’s consistent with who Alexander is.

But it also feels like manufactured drama designed to plant seeds for the Lex/Lana relationship that will eventually develop. And I have to be honest: I’ve never been on board with that relationship. The show has been planting these seeds all season, at least on Lex’s side, showing his growing attraction to Lana while she’s involved with Jason. But what’s to come feels… inappropriate at best.

There’s a power imbalance between Lex and Lana that makes their eventual romance uncomfortable to watch. He’s significantly older, exponentially wealthier, and has demonstrated repeatedly that he’s willing to use his resources to manipulate people into doing what he wants. The fact that Alexander’s first instinct when attracted to Lana is to use financial coercion tells us everything we need to know about how unhealthy that dynamic will be.

Lana’s agency in hiding the Crystal of Air from both Jason and the Luthors is a welcome development, showing her taking strategic control of her own situation rather than being a passive victim of everyone else’s schemes. But even this moment is undercut by the fact that she immediately has to deal with Alexander’s aggressive advances. Lana can never quite escape being an object of male desire that drives plot rather than a fully realized character with her own complete arc.

Jonathan Kent: Professional Victim

I need to briefly address Alexander shooting Jonathan in the leg during the barn confrontation. I get what the show was going for—raising the stakes, showing that Alexander is willing to hurt people Clark loves, creating genuine danger in the scene. And Jonathan throwing himself in front of Martha when Alexander pulls the gun is perfectly in character for him.

But can we talk about how often Jonathan is forced to play the victim in this show? He’s had heart attacks, been possessed, been beaten up, been hospitalized more times than I can count. At some point, it starts to feel less like “stakes-raising” and more like “the writers need someone to be in danger and Jonathan’s the easiest target.” John Schneider deserves better than being the show’s perpetual damsel in distress.

Convenient Solutions and Comic Book Logic

The resolution to the episode—Clark using his heat vision to transform the green kryptonite in Alexander’s ring into black kryptonite, which then re-merges the two Lexes—is pure comic book convenience. Does it make scientific sense? Absolutely not. Does it work dramatically? Mostly.

The internal logic is consistent with what the episode established: black kryptonite split Lex, so more black kryptonite merges him back together. And there’s something poetic about Clark using his own abilities to restore his friend to wholeness, to literally make Lex complete again. It’s another example of Clark’s fundamental optimism—he believes that integrated Lex, with access to both his light and dark sides, will choose to be good.

But it is awfully convenient that Clark just happens to remember that heat vision transformed green kryptonite into black kryptonite in “Crusade,” and that he’s able to execute this transformation with precision while weakened by Alexander’s kryptonite ring. The show has never been particularly concerned with scientific rigor (it’s a series about aliens and meteor rocks, after all), but sometimes the conveniences pile up enough to break immersion.

The Iron Mask and Theatrical Evil

The scene where Alexander imprisons good Lex in the wine cellar, forcing an iron mask over his head while monologuing about The Man in the Iron Mask, is deliciously theatrical. “It’s good to be the king,” Alexander declares, and you can hear Rosenbaum’s obvious delight in playing someone who gets to be this openly villainous.

Does it work as character insight? Absolutely. It tells us that even Lex’s evil side is educated, cultured, steeped in literature and history. The reference to King Louis XIV imprisoning his twin brother because “he couldn’t stand looking at such a pale reflection of his own greatness” is perfectly chosen—it speaks to Lex’s vanity, his need to be exceptional, his inability to tolerate weakness even in himself.

But it’s also almost too theatrical, tipping toward the campy when the episode works best in its more grounded moments. The image of good Lex imprisoned in an iron mask is visually striking, but it also underlines just how much this episode is a comic book premise trying to explore serious themes about identity and morality.

Tonal Whiplash in Season 4

Coming off “Lucy,” which I praised for being grounded and character-driven, “Onyx” represents another example of Season 4’s tonal inconsistency. One week we’re dealing with realistic family drama and financial troubles; the next week we have split personalities and evil twins. It’s the kind of whiplash that has defined this season—moments of genuine character insight alternating with high-concept fantasy premises that don’t always land.

But here’s the thing: I actually appreciate what “Onyx” is trying to do. The concept of exploring Lex’s dark side and his potential for evil is fascinating, even if the execution isn’t always perfect. And unlike the stones arc—which continues to spin its wheels in the background without contributing much to this episode—the split personality premise actually serves character development rather than plot mechanics.

The stones barely intrude here, which is a blessing. We get brief mentions, but they’re not driving the action. Instead, we have an episode that’s genuinely about something: about Lex’s internal struggle, about Clark’s inability to see the darkness growing in his friend, about the question of whether we’re defined by our worst impulses or our conscious choices.

The Smirk That Launched a Thousand Theories

The episode’s final moments are what linger: Lex returning to the mansion to find Lionel has reverted to his old ways, canceling the charity foundation and declaring that “a man can’t deny his true nature.” And then that smile—Lex’s cryptic, ambiguous smile in response to his father’s declaration that “we’re Luthors.”

What does that smile mean? Is it satisfaction at having his predictable villain of a father back instead of the reformed version he didn’t quite trust? Is it recognition that maybe Alexander was right, that maybe this darker path is inevitable? Is it resignation to a destiny he’s been fighting against but is tired of resisting?

The beauty of Rosenbaum’s performance is that the smile could mean all of these things or none of them. It’s the smile of someone acknowledging an uncomfortable truth, even if he’s not quite ready to act on it yet. It’s the smile of someone standing at a crossroads, still uncertain which path he’ll take but increasingly aware that the decision is coming.

I don’t think this is where Lex’s true turn begins—that’s still ahead of us, still dependent on choices and betrayals yet to come. But it’s a moment of recognition, a foreshadowing of the transformation we all know is coming. The tragedy isn’t that Lex has an evil side that will inevitably win; it’s that he’ll choose to become the villain, step by deliberate step, even while part of him knows better.

Why “Onyx” Works (Despite Its Flaws)

“Onyx” is far from perfect. The amnesia resolution is a tired convenience. The Lana subplot plants seeds for a relationship I’m not interested in seeing bloom. Jonathan gets hurt yet again. The resolution is comic book logic at its most convenient. And the episode’s philosophical exploration of good versus evil, while interesting, sometimes oversimplifies the moral complexity that makes Lex compelling.

But what makes “Onyx” succeed despite these flaws is Michael Rosenbaum’s spectacular dual performance and the episode’s willingness to dramatize the central tension of the Clark/Lex relationship. By literalizing Lex’s internal struggle, the show gives us a preview of the villain he’ll become while reminding us of the friend he still is. By showing us both versions simultaneously, the episode forces us to confront the uncomfortable reality that both versions exist within the same person—that the capacity for great good and terrible evil can coexist in the same heart.

The question isn’t whether Lex has darkness in him. The question is whether that darkness defines him, or whether he has the strength to choose differently. “Onyx” suggests that the jury is still out, that Lex’s fate isn’t sealed despite Alexander’s conviction otherwise. But that cryptic smile at the end tells us that the scales are tipping, that the man who crashed into river and was saved by a strange boy with impossible powers is slowly transforming into the man who will become that boy’s greatest enemy.

It’s not a perfect episode, but it’s a fascinating one—a comic book premise in service of character exploration, a high-concept fantasy used to examine recognizable human struggles with identity, morality, and destiny. And in a season that has too often prioritized mythology over character, “Onyx” reminds us that Smallville works best when it uses its fantastic elements to illuminate the very human story of a boy becoming Superman and a friend becoming the villain.

What are your thoughts on “Onyx”? Does Michael Rosenbaum’s dual performance work for you, or does the split personality concept feel too gimmicky? How tired are you of people discovering Clark’s secret and then forgetting it? And do you think this episode marks a turning point in Lex’s moral trajectory, or is the real transformation still ahead? Share your memories and theories in the comments below!