Recent storylines revealed that she was once engaged to be married to the King of Xebel known as Nereus, but the rumor suggests that will be changed significantly, and that Mera will actually be the king's daughter in Aquaman.
Diehard comic book fans might be upset at the change, though it makes sense given the age discrepancies between actors Amber Heard and Dolph Lundgren, who will play Mera and Nereus respectively.
Instead of doing a love-triangle storyline, it will likely involve divided loyalties as Mera is torn between Atlantis and Xebel.
In the New 52 continuity, Mera left Xebel and began a relationship with Arthur. After the Dead King arrived and tried to unite the seven kingdoms under his rule, Mera tried to warn the Xebel forces but was instead betrayed by Nereus.
It seems like there will be a variation of this storyline in the film, though it remains to be seen as director James Wan has kept the plot details of Aquaman tightly under wraps.
Mera and Aquaman made their big screen splashes in Justice League, where Arthur Curry was revealed to be an outcast of the underwater kingdom. She praises Arthur's birth mother and owes a debt to her, but Arthur seems careless about his Atlantean heritage.
We know that Orm, AKA the Ocean Master, will be the king in the new film, though he might not be a benevolent ruler. Actor Jason Momoa revealed the fleet of underwater forces in the San Diego Comic-Con teaser belonged to Orm, meaning he might be planning an invasion of some kind.
Whether Orm is the one intending to unite the seven kingdoms of the ocean and rule over all as the king remains to be seen, but it could be a source of the conflict driving forward.
It would also bring Arthur into play as a rightful challenger to the throne of Atlantis and one of the few who can stop his brother. And of course, that could put Mera in a precarious position as her loyalties are divided between her adopted home in Atlantis, her birth home in Xebel, and her sense of right and wrong.
Hopefully we learn more about Aquaman in the coming months as the movie gears up for its premiere on December 21st.
(h/t the Aquaman Shrine)