Fox has already scheduled an X-Men sequel for 2016 and a third Wolverine film for the following year. It has announced planned spinoffs, including one featuring X-Force, a darker, militaristic cadre of mutants in the comics.
It's also injecting star power into the franchise. Producer Lauren Shuler Donner announced at the U.S. premiere that Channing Tatum will join the cast of "X-Men: Apocalypse" in 2016 in the role of fan-favorite Gambit. On the Australian red carpet, Hugh Jackman told IGN he was less sure he would leave the franchise as planned, saying the series feels fresher than ever.
Mutants won't be the only heroes in Fox's universe, either. The studio will take a second crack at its "Fantastic Four" franchise next year, rebooting the exploits of the super-powered family of space explorers.
The excitement Marvel has generated around its brands following the successful Avengers films could give the X-Men and Fantastic Four a boost. But the movies have also set a high bar, and though the Marvel characters are allies in the comics, they're bitter rivals at the box office. Were either Fox franchise to fail, the silver lining might shine brightest on Marvel.
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"Those rights mean you have to make those movies, otherwise they revert back to Marvel. And in this case that means Disney," Bock said. "So you're giving it right back to your competitors. Certainly you don't want to do that."
Other films could make it a turnaround year for Fox. Dreamworks' "How to Train Your Dragon 2" has little animated competition this summer. "Dawn of the Planet of the Apes" is another sequel with a successful predecessor.
"The Fault in Our Stars," based on a young adult romance, could attract women given the dearth of female-skewing films this summer, said Bock, but "Maze Runner" will struggle, as have other dystopian YA adaptations beyond The Hunger Games series.
In October, Fox releases a screen version of best-selling book "Gone Girl" starring Ben Affleck and directed by David Fincher, the hit-maker behind "House of Cards" and "The Social Network."
—By CNBC's Tom DiChristopher.