X-Men: Apocalypse is yet to premiere but spoilers about the movie keep coming in to excite its fans.

The latest spoiler suggests that in order to promote the highly anticipated movie, Fox will use the viral marketing method, and to start with the production company has released two viral websites TandemInitiative.com and M-Underground.com.

The websites, though normal looking, have some insider plot information about the fan favourite movie.

CinemaBlend suspects that the information on the website M-Underground has huge plot spoilers, and that the upcoming movie will explain the Kennedy Curse on mutants.

"Through their own investigative journalism, it has been revealed that the late Senator Ted Kennedy's plane crash in 1964, as well as his 'original' draft of the speech he gave at the 1978 Democratic National Convention, are both tied to his mutant abilities in some sort of secret history that might explain the Kennedy Curse as a mutant hate crime of the largest scale," the website report reads.

Meanwhile, the movie writer Simon Kinsberg confirmed that the characters of Storm, Phoenix and Cyclops will be coming back but Halle Berry, Famke Jannsen and James Marsden may not return to reprise their roles as the characters will be replaced by younger actors.

"It'd be very hard to do, because Halle, Famke, and Jimmy and others have done such wonderful jobs of bringing those characters to life," Kinberg told Yahoo. "But I also would have said before First Class that there would be no actors who can stand alongside Ian McKellan and Patrick Stewart."

The next instalment of the blockbuster mutant movie takes place 20 years before the first X-Men movie and fans expect the characters of the first movie to reappear again in the movie which is set for a 2016 premiere.