A bunch of set photos from the filming of Ms. Marvel recently leaked online, showing Iman Vellani in civilian clothing as Kamala Khan riding a bike next to another actor, assumed to be Matt Lintz, playing Kamala's best friend from the comics, Bruno Carrelli.
The photos that have gotten the most attention show Kamala Khan wearing a Captain Marvel costume, inspired by Danvers outfit seen in Avengers: Endgame, for what appears to be Halloween time. However, many fans noticed that Kamala wasn't the only one wearing a costume in honor of their favorite superhero.
As pointed out by multiple users on Twitter yesterday, it seems like Bruno dressed up as Bruce Banner, alongside Kamala's own Captain Marvel costume.
WHAT THIS MEANS
It seems very apparent at this point that Kamala and Bruno are going out for Halloween, both seemingly dressed as their favorite heroes. Kamala was wearing what appeared to be a home-made costume of Captain Marvel's outfit seen in Avengers: Endgame, and Bruno seems to be emulating Bruce Banner, which is more apparent when comparing his appearance in Avengers: Age of Ultron.
Kamala is dressed up as Carol Danvers, so Bruno dressing up as another hero alongside her makes a lot of sense. In the comics, Bruno is actually an aspiring scientist, specifically in the chemical engineering field, so it wouldn't be a stretch for him to see Bruce Banner as his personal hero, being a famous scientist who doubles as a superhero. Additionally, at least at Peter Parker's school in Spider-Man: Homecoming, Bruce Banner is comparable to Marie Curie and Sir Isaac Newton.
Such a reference bodes well for other MCU connections in Ms. Marvel when the series debuts on Disney+ in 2022.