According to writer Simon Kinberg, X-Men: Apocalypse will take place in 1983.
The much awaited film, will act as a follow up to X-Men: Days of Future Past, set ten years after the events of that film. Kinberg in a Q and A pod cast with Jegg Goldsmith revealed certain plot points while also discussing the big question as to whether the fan favourites Cyclops, Jean Grey and Storm would in fact appear in the film.
"Young Cyclops could be in the seventies. He could be in future X-Men movies in the past. In terms of the math, (Storm, Jean Grey and Cyclops) would be in their early teens." He said after confirming, "The next movie takes place in 1983."
X-Men: Apocalypse as the name suggests will definitely centre around the immortal mutant Apocalypse, who is a consistent bane in the X-Men's side, in the comics. Now to those familiar with the comics, Apocalypse (En Sabah Nur) is one of the Marvel Universe's most powerful villains often coming to blows with the X-Men since his introduction in X-Factor #05.
The theory that the plot will revolve around the most prominent Apocalypse story-line - Age of Apocalypse, is making rounds on the Internet, but considering the plot in the comics is based on time travel, it doesn't seem likely. Seeing as how Days of Future Past had a fair amount of time travel, it would be difficult, not to mention confusing to pull off. It's more likly that he simply be introduced as the primary antagonist in the film; which would pit the X-Men against one of their most formidable foes. Apart from his near immorality, superhuman strength, teleportation, technopathy and other assortment of powers, he is also a master strategist and has a genius level intellect that possibly rivals Bruce Banner and Reed Richard.
The comic story-line Age of Apocalypse was extremely well received by critics and fans alike and features major changes in an alternate timeline. The plot of the story revolves around Legion, the son of Charles Xavier travelling back to the time when Xavier and Eric Lehnsherr (Magneto) were still friends with the intention of killing him. However Xavier dies, sacrificing himself to save Magneto and the timeline gets disrupted. It is at this moment that Apocalypse decides to strike and take control of the world. Many of the X-Men's paths change due to this alteration in the timeline, including Wolverine, Cyclops, Jean Grey, Gambit, Rogue, Kitty Pryde, Collosus, Iceman and Magneto himself.
As with the previous film, X-Men: Apocalyse is expected to focus on the younger versions of the characters once again, and Channing Tatum could join the fold as the Cajun theif Gambit.
X-Men: Apocalypse hits theatres on 27 May, 2016.