The Superman trailer may have just revealed exactly how Lex Luthor gets his hands on Kal-El’s biggest weakness, spawning a theory about how he could take advantage of it. James Gunn’s Superman movie is in the final stages of its marketing as its July 11 release date grows ever closer. This led DC Studios to release the official trailer for Superman in May 2025, providing audiences with what is presumably the last extended look at the first true movie installment of the DC Universe.

In the trailer, several elements of the upcoming DCU movie were highlighted. Be it the chemistry between Clark Kent and Lois Lane, the morals of Superman and the tribulations he must overcome to enact those beliefs, or the many villains of Superman, the trailer provided the best look yet at what is set to be the DCU’s first step. Where those villains are concerned, Superman‘s trailer gave more hints at Lex Luthor’s plan, including the reveal of how Kal-El’s archenemy will gain access to the latter’s biggest weakness, allowing me to form a theory of how the former can exploit this.

Superman’s Trailer Appears To Show Metamorpho Creating Kryptonite

The Interesting Character Will Play A More Vital Role Than First Thought

The trailer for Superman showcased a lot of the heroes that will play a part in the film, as well as its villains. Aside from the likes of Guy Gardner, Hawkgirl, and Mister Terrific, perhaps the most intriguing – and least highlighted – DC hero in Superman is Metamorpho. Played by Anthony Carrigan in Superman‘s ensemble cast, Metamorpho is a reluctant hero named Rex Mason who unwittingly receives the power to transmute his body into any chemical, as shown in the trailer.

Interestingly, one sH๏τ in Superman‘s official trailer shows Metamorpho in prison alongside Superman. When looking at Metamorpho’s left arm, it is glowing green. This indicates that Metamorpho is transmuting his body to create Kryptonite for Lex Luthor, explaining why the robots in the same scene are able to injure Kal-El.

Based On Superman’s Trailer, I Think I Know How Lex Luthor Gets Unlimited Kryptonite

Linked To Metamorpho’s DC Comics Stories

Stemming from this scene, I think I know how Lex Luthor will manipulate Metamorpho into creating Kryptonite. After all, this must be how the story plays out, given that Rex Mason is usually depicted as a good guy and an ally of DC’s biggest heroes. In one sH๏τ in the trailer, specifically the one in which Superman is being attacked by the robots in the glᴀss cell, a woman can be seen in the adjoining box. This could be Sapphire Stagg, another character from DC Comics who has strong links to Metamorpho.

In the comics, Metamorpho and Sapphire Stagg have a long-lasting relationship. It could be the case that Lex Luthor has kidnapped both Sapphire and Metamorpho, threatening the former with harm if the latter does not create Kryptonite and help to weaken Superman. This would explain why the usually benevolent Rex Mason would help Lex, all while allowing Superman‘s main enemy to obtain the means of injuring the Kryptonian hero.

Other Aspects Of Superman’s Marketing Support This Metamorpho Theory

Metamorpho’s Dark Story Looks More Likely Than Ever

What makes this theory all the more promising is the confirmation that the Stagg family will play a role in Superman. While casting news for these characters has not been unveiled, a sH๏τ from Superman‘s teaser trailer showed the тιтular hero in the lobby of Stagg Industries. In the comics, the owner of this company is Simon Stagg, the supervillainous father of Sapphire Stagg, whom he is intensely protective of. As a result, he hates Rex Mason and often tries to break up their relationship, even linking to Rex’s origins as Metamorpho.

If Simon and Sapphire Stagg play a role in Superman, the former could make a deal with Lex Luthor that leads to the mastermind obtaining both of them, likely via betraying Simon. If this comes to pᴀss, Lex would have a means of creating unlimited Kryptonite and a means of ensuring Metamorpho follows orders. This way, the battle between Lex Luthor and Superman would increase in scale as the two square off in the DCU for the first time.