Nicole Kidman was James Wan's top choice for the role of Atlanna. They were previously set to work together on a remake of At the End of the Spectra (2006), but the film was scrapped. Kidman has been a long time supporter of Wan's career, and has publicly raved about his films Insidious and The Conjuring, calling him "The New Master of Horror". She was also eager to join as filming took place in her homeland of Australia.
Nicole Kidman immediately accepted the role of Atlanna when James Wan said that she could wear "Mother-of-Pearl and be a Mermaid Warrior".
Nicole Kidman, who plays Aquaman's mother Queen Atlanna, had declined the role of Queen Hippolyta in Wonder Woman (2017) (in the comics, Diana Prince/Wonder Woman was Aquaman's ally and sometimes love interest).
Aquaman's suit was supposed to be a surprise in 2016. Instead, Zack Snyder released the photo of Momoa wearing the Aquaman suit in February 2015. Snyder called Momoa moments before its release to the world.
This film marks the fifth collaboration between director James Wan and actor Patrick Wilson, after Insidious (2010), The Conjuring (2013), Insidious: Chapter 2 (2013) and The Conjuring 2 (2016).
Director James Wan cites the adventure films Raiders of the Lost Ark (1981) and Romancing the Stone (1984) as an influence on the film.
James Wan revealed he had a choice of what film he wanted to direct between The Flash and Aquaman, but chose Aquaman because he is the underdog.
Jason Momoa admitted to playing pranks on all of his fellow cast members during filming except for Nicole Kidman.
Michael Kenneth Williams and Michael Jai White expressed interest in playing Black Manta.
James Wan believes that what makes Aquaman unique is his Atlantean heritage: "We're used to superhero movies where the threat is from another dimension or aliens from another universe coming here and trying to destroy our Earth. But we haven't seen one where the main threat is from a massive, massive civilization that is right under our nose, in the ocean.... The idea that there could be a massive civilization living right underneath [us] that we don't know about is kind of scary and exciting."
The film's working title is "Ahab", the name of an anti-heroic sea captain in Herman Melville's classic story "Moby Dick".
At one point, the Dead King, an ancestor of Aquaman who was resurrected as an insane zombie, was to appear in the film as an antagonist, but he was removed.
James Wan, the director, confirmed that Atlanteans won't talk inside protective speech bubbles as portrayed by Zack Snyder in Justice League. When asked he said, "People are overthinking it. They're just gonna talk!".
Jason Momoa added more blonde highlights to his hair to be closer to the original incarnations of Arthur Curry/Aquaman, who is entirely blonde in the comics.
James Wan cites the sea monster film Creature from the Black Lagoon (1954) as an influence on the portrayal of the Trench monsters.
Jason Momoa, who plays Aquaman the King of Atlantis, had starred in the TV show Stargate: Atlantis (2004).
This is Patrick Wilson's second portrayal as a comic book character first being Night Owl in Watchmen (2009)
King Nereus and Mera appear as father and daughter in the film, while they were unrelated and betrothed to marry in the New 52 comics.
According to Amber Heard, the underwater filming required cast members to be hosed down, and then shooting took place on a cold soundstage.
The Fishermen tribe were created through a combination of make-up (for the top half, the upper torso) and computer-generated imagery (for the bottom half, the tails).
This is Don Burgess' first time shooting a superhero movie since Spider-Man (2002).
One rumor was saying that Mera was going to be non-Caucasian to match up with Jason Momoa's mixed race status who is Native Hawaiian/German, Irish and Native American, but it was put to rest when Amber Heard was cast.
Michael Beach who portrays Black Manta's father Jesse Kane in the film, had previously voiced Devil Ray (another name for Black Manta) in Justice League Unlimited (2004).
This is Graham McTavish's sixth comic-book role, after Loki (Marvel animated features), Sebastian Shaw (Wolverine and the X-Men (2008)), Savanti Romero (Teenage Mutant Ninja Turtles (2012)), Fergus McDuck (DuckTales (2017)), and the Saint of Killers (Preacher)
This is the 3rd comic book adaptation for Temuera Morrison (after Green Lantern (2011) and Barb Wire), 2nd Comic Book adaption for Nicole Kidman (after Batman Forever (1995)), Willem Dafoe (after the Sam Raimi Spider-Man films) and Dolph Lundgren (after The Punisher (1989)).
This is the first DCEU film to be shot entirely with digital cameras, all previous installments were shot on 35mm film (and partially 70mm IMAX film for Batman v Superman: Dawn of Justice (2016))
Nicole Kidman second comic-based film. She previously played Bruce Wayne's love interest in Batman Forever (1995).
Nicole Kidman attended her first Comic-Con in 2018 especially to promote this film.
Patrick Wilson and Michael Beach have worked together in Insidious: Chapter 2 (2013) which James Wan directed.
Kurt Johnstad and David Leslie Johnson worked on the script before being replaced by Will Beal.
Willem Defoe and Temura Morrison previously worked together in Speed 2: Cruise Control (1997).
Djimon Hounsou's second comic book role after Korath in Guardians of the Galaxy (2014). He also plays the Wizard in the DCEU film Shazam! (2018).