The X-Men Film Series is the second highest grossing film series based on Marvel characters following the Marvel Cinematic Universe despite the fact that some of its movies were not critically acclaimed.
X-Men: Apocalypse is the 8th installment of the franchise and it will be released in cinemas worlwide in May 27. And since the X-Men movies are quite confusing in terms of the timeline, here are some of the movies that (I think) you should probably watch before seeing X-Men: Apocalypse.
1. X-Men: First Class
Initial Release: May 25, 2011
Directed by: Matthew Vaughn
The story was set in the 1960s, in the course of Cold War's apogee, Charles Xavier, who will eventually be called as Professor X, met a fellow mutant in the name of Erik Lehnsherr, soon will be Magneto. Even though Charles and Erik came from different backgrounds, with Charles living his life with a golden spoon in his mouth while Erik lost his parents in Auschwitz, the two in due course become close friends. As the world lurches into the brink of war, Charles and Erik together with their fellow mutants joined forces to save humanity. However, a circumstance soon pull the friends apart.
X-Men: First Class is a must-watch movie before seeing X-Men: Apocalypse because it embarked the beginning of X-Men and it will help you rediscover what happened to Charles and Erik before they became the enemies we know now.
2. X-Men: Days of Future Past
Initial Release: May 10, 2014
Directed by: Bryan Singer
In the future, set in the 2023, robots known as Sentinels which can detect a mutant gene, terminates all mutants and all its allies. It was developed in the 1970s by a military scientist named Dr. Bolivar Trask for he was convinced that mutants serve as a threat to the human race. Kitty Pryde sent Logan back in the year 1973 to prevent Mystique from assassinating Trask because it proved the people that mutants pose a threat in humanity so they will use Mystique's DNA to improve the Sentinels, giving the ability to adapt to any mutant power that will make them almost indestructible. Wolverine, together with the X-Men from the past, help change a decisive moment in the olden days for a better and brighter future.
In spite of being the prequel to the latest X-Men movie, Days of Future Past is a movie you should watch before checking out X-Men: Apocalypse because it was set ten years before Apocalypse takes place and it also serves as the 'soft reboot' of the franchise, making all of the first three movies (X-Men, X2 and X-Men: The Last Stand) irrelevant. In addition, some of the scenes that will be featured in X-Men: Apocalypse are derived from what occurred in Days of Future Past.
3. X-Men Origins: Wolverine
Initial Release: April 30, 2009
Directed by: Gavin Hood
Okay, this movie might be the least favorite among all the X-Men movies but the reason why you should rewatch or watch this movie is because in the final trailer of X-Men: Apocalypse, we had a glimpse of the Alkali Lake, William Stryker and the Weapon X program which are all part of Wolverine's origin. Forget the crappy visual effects, Deadpool and the underrated Gambit in this movie. As long as you learned how Wolverine became a part of the Weapon X program, you'll surely have an idea on why he his appearing in X-Men: Apocalypse.
And to wrap it all up, aside from Nightcrawler who appeared in X2 and Angel who came out in X-Men: The Last Stand, some of the cast from these movies will be appearing in X-Men: Apocalypse. Besides, they might change the approach to Nightcrawler and Angel in this movie so don't bother watching X2 and The Last Stand because you'll just confuse yourself.