The shapeshifter’s son? Superman’s mysterious Baby Joey and the storyline possibilities explored

Who is Baby Joey?

He doesn’t speak. He doesn’t fly. He doesn’t even wear a cape. But Baby Joey is already one of the most talked-about new characters in James Gunn’s Superman, and the kid hasn’t even shown up on screen.

All it took was a tie-in children’s book, a few toy leaks, and a name: Joseph Mason. If that sounds familiar to DC fans, it should. Joseph is the son of Rex Mason, better known as Metamorpho, the Element Man, and Sapphire Stagg, heiress of Stagg Industries.

That lineage alone would be enough to make the baby interesting. But Gunn’s DCU isn’t just bringing Joey in as background lore. From everything we’ve seen so far, this baby is going to matter.

The reveal came via Superman’s Friends and Foes, a children’s book that introduces kids to the major characters of the film. Nestled among descriptions of Luthor, Superman and Lois Lane was a quiet bombshell: Baby Joey is not just someone’s baby. He’s the baby, the one Lex Luthor kidnaps to get Metamorpho under his thumb.

Suddenly, this odd little character has stakes. He's not a wink to comic readers or a walking Easter egg. He’s a pawn in a power game between a billionaire supervillain and a man who can reshape his own body into any element on the periodic table. And for the first time, Superman’s new era is signaling what kind of stories it's really here to tell.

A shapeshifter’s legacy

Joey Mason might not look like much now, but his DNA tells a different story. He’s the offspring of a man who dissolved, exploded and reconstituted himself into walking chemistry.

Rex Mason didn’t ask to become Metamorpho. He was caught in an alchemical accident, sculpted into something half myth, half science. A body no longer made of flesh and bone, but of gas and minerals, magma and metal.

That’s the inheritance passed down to Baby Joey, an unpredictable cocktail of elemental transformation and unstable genius, wrapped in the soft frame of an infant who doesn’t yet know he’s dangerous.

In the comics, Joey mutates his father’s powers. Where Metamorpho reshapes his body, Baby Joey shifts the atomic structure of objects around him. He’s not a mimic. He’s a force of change.

This is the kind of ability that sounds quiet on paper until you realize what it means in practice: molecular disruption, elemental reprogramming, the power to rewrite the laws of matter with a touch.

No flight, no heat vision. Just the physics of the world unraveling in his wake. It’s absurd, elegant and terrifying, and exactly the kind of twist Gunn’s DCU would sink its teeth into.

Lex Luthor’s cruel plan

No version of Lex Luthor does anything by accident. In James Gunn’s Superman, the villain seems to be targeting the vulnerable. And Baby Joey, for all his genetic potential, is as vulnerable as it gets.

Promotional materials already confirm that Luthor kidnaps Joey as a way to force Metamorpho into compliance. That’s not a small-time villain move. That’s the playbook of someone who understands the emotional leverage of a child better than any sci-fi MacGuffin. If Rex Mason is a man shaped by transformation, Luthor is a man who weaponizes it.

But there’s another layer here. It’s not just about coercion. Metamorpho’s powers can be horrifying when redirected. In the comics, he’s turned himself into gases, acids, even radioactive materials.

Imagine what happens when Luthor pushes that to its extreme. If he can manipulate Metamorpho into producing kryptonite, whether directly or by using Joey as leverage, he gains a weapon no amount of hope or heroism can withstand.

A baby becomes the trigger for biochemical warfare. A father becomes the reluctant dealer of Superman’s only weakness. And Luthor? He doesn’t have to get his hands dirty. He just has to smile and wait.

The baby’s future in the DCU

He might just be a crying bundle in this first chapter, but Joey Mason is already a narrative time bomb. James Gunn doesn’t plant characters without intention, and a child born of elemental chaos is not just set dressing. It’s setup.

Joey’s existence opens a dozen doors for the DCU to walk through, and some of them lead straight into science fiction horror. Powers like his could evolve in unexpected ways. Maybe he’s a sleeper agent of mutation. Maybe the molecular instability inherited from his father makes him too dangerous to grow up the usual way. Or maybe, like so many DC characters before him, Joey won’t stay a baby for long.

The trope of rapid aging isn’t new. We’ve seen it with characters like Damian Wayne, Kon-El, even Franklin Richards across the comic multiverse. Joey could age up for narrative reasons, giving Gunn a teenage metahuman with deep emotional roots and built-in trauma.

But even if they keep him young, his mere presence creates tension. He’s the son of a reluctant hero, born into a world that turns vulnerability into leverage. That alone could place him at the center of future conflicts, especially in a universe where people like Amanda Waller are known to weaponize childhood before it ever becomes adulthood.

Joey might be too small to fight now, but someone is already deciding what kind of soldier he could become.

Baby Joey and the spirit of James Gunn’s DC

This is exactly the kind of character James Gunn loves. Weird. Vulnerable. Slightly absurd. Deeply human. Baby Joey isn’t just a hostage or a plot trigger. He’s a quiet thesis statement.

From Guardians of the Galaxy to The Suicide Squad, Gunn has built a reputation on giving weight to the characters everyone else would leave on the cutting room floor. Talking trees. Rats with heart. Genetic monstrosities that cry. He writes emotional anchors wrapped in creature features, and Joey fits that mold perfectly.

There’s something undeniably Gunn about putting a baby at the emotional core of a film filled with gods, mutants and billionaires. It’s a move that disrupts the usual superhero formula and turns a high-stakes action epic into something stranger and more intimate.

Joey’s presence brings pathos into the chaos. He isn’t strong. He isn’t in control. But the story begins to orbit him anyway. That’s how Gunn signals where the heart of the film truly lies, not in the fists or the capes, but in the quiet weight of what could be lost.

More than just a baby: Baby Joey’s symbolic weight in Superman

Superman stories have always carried the burden of myth. They’re about strength, sacrifice, hope, but also about fear of what we can’t control. In that landscape, Baby Joey is more than a plot complication.

He’s a metaphor wrapped in a pacifier. A child born of transformation, taken by force, turned into leverage, he embodies everything Superman is supposed to protect. Not a planet, not an ideal, but a life too small to defend itself. That’s where Gunn’s approach becomes clear. This isn’t a story about saving the world. It’s a story about who gets crushed when the world is at war with itself.

Baby Joey may never throw a punch, never speak a word, never put on a suit. But his presence reshapes the moral landscape around him. He forces characters like Metamorpho to choose between power and family, and forces Superman to reckon with the consequences of his very existence.

Baby Joey is a reminder that innocence is rare. And in Gunn’s Superman, that makes him the most dangerous character of all, the one everyone underestimates until it’s far too late.