Image source: Fox

X-Men Apocalypse is an extra-important movie for Fox (NASDAQ:FOX) (NASDAQ:FOXA). After a run of disappointing releases in 2015, and repeated delays for the Avatar sequels, the upcoming X-Men film will do a lot to determine the strength of the company's film slate. The May 27 release is even more important as Fox looks to its film segment to counterbalance trouble in TV-land.

The superhero movie universe has become a key part of success for big film studios, and major genre releases from Time Warner and Disney (NYSE:DIS) are also vying for audience attention and dollars this year. Will Fox's superhero team once again prove to be extraordinary? And what happens if Apocalypse shrinks at the box office rather than explodes?

The X-Men lead Fox's big 2016 push
2016 is a crucial year for Fox's film division. Between X-Men: Apocalypse, Ice Age: Collision Course, and Independence Day: Resurgence, the year will see Fox release a movie in all of its most valuable movie franchises except Avatar. Keeping the Ice Age series alive is important, and Independence Day has big breakout potential and could restart the franchise, but the power that expanded superhero film universes have over today's theatergoers makes Apocalypse Fox's most important film in a stacked release year.

The Avatar series is Fox's most explosive movie property, but production of the three upcoming sequels has already been a lengthy affair, and the company could really use a successful superhero universe to strengthen its lineup over the next decade -- particularly as James Cameron can be counted on to take his time perfecting the upcoming Avatar releases. Throw in the fact that Fox's recent Fantastic Four reboot cratered at the box office, and the significance of the upcoming X-Men film is even more apparent.

What does the path to success look like for Apocalypse?
Fox's next mainline X-Men film has the benefit of following up 2014's X-Men: Days of Future Past, a film which grossed roughly $750 million at the global box office and won rave reviews from critics and audiences alike. The series looks to have strong momentum in international markets, particularly China, which does a lot to improve Apocalypse's chance of surpassing its immediate predecessor's ticket sales.

The cards aren't all stacked in Fox and the X-Men's favor, however. Relative to Days of Future Past, Apocalypse will have less star-power, with fan favorites Ian McKellan and Patrick Stewart presumably absent from the picture, and what looks to be a smaller role for series star Hugh Jackman. The Wolverine character, as portrayed by Jackman, has been central to all-but-one of Fox's X-Men films, and the only film in the series not to feature Jackman in the lead was less-than-stellar at the box office.

Jackman will have a front-and-center role in 2017's The Wolverine, but the actor has made clear that he expects it to be his last turn as Weapon X. The departure of the franchise's biggest star looms even larger thanks to comments from co-star Jennifer Lawrence indicating that Apocalypse will also be her last X-Men film.

It's X-Men vs. Alice in a Memorial Day weekend showdown
In addition to not featuring Jackman in the lead role, Apocalypse will also need to overcome formidable competition in order to achieve box office glory. In America, Fox's picture will launch the same day as Disney's Alice Through the Looking Glass -- the follow-up to the company's $1-billion-grossing Alice in Wonderland from 2010.

While the two pictures are targeting somewhat different segments of the film-going public, releasing the same weekend almost certainly limits each film's upper sales potential in the domestic market. Having two massively budgeted, would-be blockbusters competing in the same opening frame is pretty much unheard of -- and the fact that X-Men is more important to Fox than Alice is to Disney makes The House of Mouse the likely winner of this release timing showdown.

Disney has an interest in moving public attention away from Fox's X-Men series in order to maintain superhero supremacy, and it's possible that this aim played a role in setting up an opening weekend showdown between Alice and the X-Men.

What comes after Apocalypse?
Apocalypse isn't the next movie to release in Fox's X-Men universe -- that distinction belongs to February's Deadpool, but it is certainly the most important. With key franchise talent leaving the series, Apocalypse has to be the springboard for a new wave of X-Men stories and characters. Fox's film business looks a lot stronger if this proposition is successful.

Perhaps most importantly, Channing Tatum's Gambit character will make his debut in Apocalypse, before receiving a solo film in October. Tatum and Gambit could help establish a new franchise lead as Jackman's Wolverine exits the picture -- and Fox's New Mutants, one of many projects that the company is working on in the X-Men universe, will also be affected by how Apocalypse is received.

With so many movies tied to the upcoming X-Men film's performance, Fox's future at the movies is riding on Apocalypse.