Spider-Man: Brand New Day is quickly becoming one of the MCU’s most talked-about films. And it’s not just because Tom Holland’s Peter Parker is back for a fourth film. Fans have been trying to guess the film’s villain for months, throwing around popular names like Venom, Knull, Morlun, Hulk, and Punisher. But a new theory gaining traction online points to a Marvel character who hasn’t shown up in the Marvel Cinematic Universe yet: Alistair Smythe, the Spider-Slayer.
Directed by Destin Daniel Cretton, who also helmed Shang-Chi and the Legend of the Ten Rings, Spider-Man: Brand New Day is currently in production and will hit U.S. theatres on July 31, 2026, landing a few months before Avengers: Doomsday. After teasing his retirement, fans were happy to learn that Tom Holland will reprise his role as Spidey, and Michael Mando’s Mac Gargan (a.k.a. Scorpion) will return for his first appearance since 2017’s Spider-Man: Homecoming. Still, Scorpion isn’t expected to be the main antagonist. Instead, he’ll probably fight alongside him.
The Alistair Smythe theory started gaining momentum after costume prop modeler Monica Avitto posted a mysterious “moodboard” for the Brand New Day villain. While some thought the images hinted at Silver Samurai, another popular Marvel villain, social media user @DrawsTom suggested it could be Alistair Smythe instead. Even scooper Daniel Richtman called it a “great” theory, though Marvel and Sony haven’t confirmed anything yet.
For those who missed his comic book debut in 1985’s The Amazing Spider-Man Annual #19, Smythe inherited the Spider-Slayer mantle from his father, Spencer Smythe. He’s a robotics genius who, after being paralyzed from the waist down, operates from within a bioorganic carapace. Over the years, Smythe has gone after both Spider-Man and J. Jonah Jameson, deploying armies of Spider-Slayers, including a face-hugging miniature model designed to tap into Spidey’s mind and a hulking six-armed version built for maximum destruction. In one classic storyline, Jameson himself took Smythe down with a baseball bat for threatening his family.
Smythe’s later comic arcs got even nastier. He rebuilt Mac Gargan into a cybernetic Scorpion, recruited a cyborg army, and even caused the death of Jameson’s wife, Marla. That’s a level of personal vendetta you can’t just gloss over in a PG-13 movie, but if Marvel wants a villain with deep Spider-Man lore, Smythe is prime material.
That said, Smythe might not be the only wildcard in the mix. Jon Bernthal has officially confirmed his return as Frank Castle/The Punisher in Brand New Day. At last month’s Washington State Summer Con, a fan congratulated Bernthal on the role, to which he replied, “Thank you,” before adding that he hopes to reference The Amazing Spider-Man #129, Punisher’s first appearance back in 1974.

Of course, Punisher’s brutal style is a tricky fit for a Spider-Man movie. Marvel has to find a way to keep Castle’s edge without turning the film into an R-rated bloodbath. Nobody’s expecting the full Netflix-level carnage here, but it’ll be interesting to see how far they push him.
All of this is happening while box office analysts are already making predictions. Luiz Fernando believes Supergirl, opening June 26, 2026, could actually outgross Spider-Man: Brand New Day, which is a bold claim considering No Way Home’s $1.921 billion haul. Whether or not Supergirl pulls off a Wonder Woman-level run, Spider-Man 4 already has fans dissecting every hint, theory, and casting leak. And Alistair Smythe’s name is now firmly in the Brand New Day conversation, too.
RELATED: MCU Fans Can’t Believe These Two Avengers Have Never Actually Met