X-Men: Apocalypse, 20th Century Fox’s followup to last year’s X-Men: Days of Future Past, has been finishing up pre-production in order to begin filming in April. Oscar Isaac (A Most Violent Year) is set to star as the movie’s titular villain and Apocalypse more recently announced the three actors who will be playing younger versions of Cyclops, Jean Grey, and Storm.

Now, in the same interview in which Fox’s movie universe architect Simon Kinberg talked about the possibility of a crossover between X-Men and Fantastic Four, the writer confirmed a certain X-Men: First Class character would be returning for Apocalypse.

While speaking to EW, Kinberg confirmed that Rose Byrne will reprise her role as Moira MacTaggert, the CIA agent and mutant ally from First Class. After the events of First Class, Byrne did not appear in Days of Future Past. Kinberg said she has a significant role in Apocalypse and that the film will further develop Moira’s relationship with Charles Xavier (James McAvoy).

Read Kinberg’s full quote:

“She’s a significant character in the movie. We ended ‘First Class’ with Charles having wiped portions of her memory of her experience with the X-Men. They are, essentially, strangers to her when she meets them… It’s certainly a rich relationship that we started to dig into in ‘First Class’, and would like to mine more in this one.”

Kinberg also said that Apocalypse will act as a completion to the character arcs of Charles, Erik Lensherr (Michael Fassbender), Raven (Jennifer Lawrence), and Hank (Nicholas Hoult) that began in First Class. Even though they’re still young – in comparison to the versions that appeared in Fox’s previous X-Men trilogy – there will be a sense of closure on the “first phase of their lives.”

Since First Class was set in the ‘60s and Days of Future Past in the ‘70s, Apocalypse will continue the trend and take place in the next decade, the ‘80s. Kinberg mentioned that the ‘80s are close to his heart and will be evident in Apocalypse. When asked if Dazzler, a mutant introduced to X-Men comics in 1980, would appear, he said it “could happen.”

Read Kinberg’s full quote:

“That’s the era that I grew up in. The music, the fashion, the videogames: We really want to integrate all of that in the movie, and have it infuse the movie with a different vibe… Could happen. We’re certainly looking at mutants that would fit into the period.”

Even if Apocalypse doesn’t introduce Dazzler, there are plenty of other ‘80s-style mutants that could fit. Both energy-firing mallrat Jubilee and telepathic ninja Psylocke had at one point or another been intended to appear in Days of Future Past but didn’t make it into the final film.

Whether or not Jubilee, Psylocke, and/or Dazzler appear in Apocalypse, they won’t be the focus of the movie. Instead, Charles, Eric, Raven, Hank, and Moira – along with Apocalypse and (possibly) Wolverine – will likely be at the forefront of the movie’s action and character drama.

However, since Apocalypse will provide some closure to their storyline, and Fox is expanding its X-Men universe with Gambit and Deadpool solo films, it’s possible that these new mutants and many others could appear elsewhere down the line.

X-Men: Apocalypse will premiere May 27th, 2016.