When Clayface was first announced, fans had many questions about this DC Universe project. Could Batman be in it? Would Matt Hagen (Tom Rhys Harries) be portrayed more as an anti-hero rather than a straight-up villain? Would we see the monster in his final, clay form? Fortunately, after weeks of theories and speculation, the film is finally out to answer most of these lingering questions.
Clayface is an R-rated body-horror film starring an iconic Batman villain. All these unnerving elements hinted that a dark ending was all but guaranteed, and that was exactly the case. However, watching the birth of a villain also raised its own set of questions that need a little explaining. But before we dive right into the ending of the DCU project and explain what it truly means, be warned: There will be spoilers for Clayface ahead. If you don't want any surprises ruined, it's best to turn away now.

Are you still here? Great, then there are two likely questions that you have in mind: First, why did Gotham City detective John Borrelli (Max Minghella) claim he reviewed footage of the "club incident" and say Matt Hagen wasn't there, even though he clearly was? Second, and most importantly, did Dr. Caitlyn Corr (Naomi Ackie) turn evil by the end of the movie? Well, it's time to break it all down.
Why Matt Hagen turned into Clayface
Before he turned into a shape-shifting monster, Matt Hagen was a rising actor with all the potential in the world. He was nominated for an Academy Award; he was filming a new film, and everyone across Gotham recognized him. Unfortunately, his entire life would change due to one bad decision at a party. Matt starts to dance with Mia Torres (Joana Ribeiro), fully knowing she is the girlfriend of Gotham City mob boss Markos Szabo (David Dencik).
Things go from bad to worse when Matt and Mia sleep together. When the rising actor wakes up the next day, he's surrounded by various henchmen and Markos Szabo himself, who decides to get a little payback and cuts Matt's face in the spot. To make matters more complicated, Mia testifies that Matt harassed her during the party; Matt's manager, Frank Fitzpatrick (Eddie Marsan), took all of the actor's money; and all the surgeries Matt underwent to recover his face only made him look worse.
Desperate to regain what he once lost, Matt opts to look for a cure in a more "unethical" way. He reads about Dr. Caitlyn Corr's research, which uses nanocells to restore and regenerate lost tissue, and volunteers himself for human trials. Caitlyn refuses at first, claiming her investigation wasn't advanced enough to test in humans. Despite being disappointed, Matt still thanks her for chatting with him, does a little bow, and walks out of her lab.
The nightmare could've been prevented right there and then. However, Caitlyn was also between a rock and a hard place, given that she had lost all investment in her research and couldn't keep it going much longer. So, days later, she had no option but to accept Matt's help.
At first, the treatment appears to work wonders. Caitlyn explains that such a miraculous result is thanks to the nanocells, which are powered by AI. She even reveals that she can shut these cells down at any moment with the press of a button. Over time, Matt's scars disappear, and he even decides to make a public appearance, letting the entire media know he's back. However, he quickly realizes something's wrong with him. Whenever he feels a strong emotion like anger, his face appears to completely melt and even disappear, as if it were made of clay. Naturally, this didn't bode well for someone who had to act for a living.
Dr. Caitlyn always kept tabs on Matt's treatment and tried to help him when things went awry. The first time the actor suffered a "meltdown," she injected him with even more nanocells to try to stabilize his situation. So the second time the actor lost control of his body, he decided to go to the Dr.'s lab and inject himself with a very dangerous amount of nanocells.
As simple as that, Matt was set on a path to become a dangerous villain, especially after he decided to get revenge on all the people who stole his life in the first place, including Frank Fitzpatrick, Mia Torres, and, of course, Markos Szabo and his henchmen.
When Matt learns that Markos Szabo opened a club in Gotham City, he decides to pay the place a visit. In there, he slowly makes his way to the head of the operation, shape-shifting into different people to confuse security and killing many in the process. When he gets to the dance floor, there's a moment where he doesn't disguise himself as anyone else, letting the entire world know Matt Hagen was at the crime scene. Eventually, he finally made his way to the club's main office and killed Markos Szabo and Mia Torres.

Matt Hagen turned into detective John Borrelli in the final sequence to see if Caitlyn was in love with him
All throughout the events of Clayface, audiences see Dr. Caitlyn Corr genuinely worry about Matt and do her best to help him with the treatment. At first, she didn't know that the former actor was using his newfound powers to shapeshift and go on a killing spree. And since the two spent so much time together, celebrating their victories and supporting each other, they started to develop feelings for one another.
However, there was one major problem with their dynamic. Dr. Caitlyn was engaged to Gotham City detective John Borrelli—one of the only "clean" cops in the city. And since John was the only person standing between Matt and Caitlyn, things were bound to take a dark turn.
John Borrelli began investigating the sudden murders in the city and quickly realized there was one connection between them: They victims all wronged Matt Hagen. Naturally, the detective decided to have a quick chat with Matt in an attempt to uncover whether he was a killer in disguise or not, and while this conversation was part of Borrelli's job, it ultimately sealed his fate.
After Dr. Caitlyn learns about the assassinations at Markos Szabo's club, she starts to piece together that Matt had been the true killer all along. Immediately after, she goes to her lab, grabs all the evidence she can that proves Matt has the ability to shape-shift, and then rushes back home to tell her fiancé what's truly going on.
When Caitlyn finally arrives home, she confesses to John Borrelli that Matt Hagen could be the primary suspect behind the murders. Borrelli then says he also used to think the same, but that he looked at the security footage of Markos Szabo's club and Matt wasn't there at any point when the killing spree happened. This is a bit contradictory, since Matt was in the club, and he showed his true face there. So how come Gotham's only honorable detective missed this clue? Well, because it wasn't the detective at all. Turns out, it was Matt Hagen in disguise, while the real John Borrelli was dead in Caitlyn's living room. Matt simply wanted to see how Caitlyn "looked" at her fiancé, to figure out whether she loved him or not.

Dr. Caitlyn Corr isn't evil, and she's aware that Matt Hagen is still alive
When Caitlyn Corr learns that Matt killed her fiancé, John Borrelli, and took his place for a while, she is naturally horrified. She uses a taser to defend herself and kick Matt out of the house. Furthermore, she then presses the "shutdown" button to power down the nanocells in Matt's body that give him the ability to shape-shift. It is at that very moment, when Matt's body starts to contort and nearly explode, that we finally see Clayface in his true, final form.
Eventually, Matt's whole body "melts" and is dragged into the sewers, seemingly putting an end to the nightmare. But as was to be expected, things aren't so simple in Gotham City. Days later, Dr. Cailtyn walks in the streets and starts looking around her, suspecting anyone could potentially be Matt Hagen in disguise. However, she comes across a homeless man who asks her for a coin, and when she gives it to him, the man bows in appreciation. This mannerism completely mimics how Matt Hagen once bowed to Caitlyn to thank her for having a chat with him. As simple as that, Dr. Caitlyn knows Matt's still alive somewhere.
The final sequence of the film showcases Matt Hagen hidden in the sewers when, all of a sudden, Dr. Caitlyn approaches from behind and starts to congratulate him on the rave reviews he received for his latest film performance. The two kiss, and the film comes to an end. So, does that mean Caitlyn followed the homeless man to the sewers, had a change of heart, and decided she wanted to be with Matt? No. One of Matt's abilities is to separate pieces of his body from himself, so he separated a large chunk from himself and shape-shifted it into Dr. Caitlyn. What we saw was Matt talking to a piece of himself.
This final sequence is meant to showcase how broken his psyche truly is. He's still obsessed with the doctor who gave him his abilities, and he's merely acting as if Caitlyn were next to him, when in reality, she wasn't. The villain was merely putting on the performance of a lifetime.
Clayface is now playing in theaters.
