X-Men Cinematic Universe Movies.

With the summer release of X-Men: Apocalypse behind it and a Deadpool sequel hitting a speed bump, 20th Century Fox is finding its superhero franchise at another type of X: a crossroads.

Fox has had movie rights to Marvel's X-Men characters since the 1990s, well before Marvel became its own studio and Fox ostensibly launched the modern comic book movie with 2000's X-Men. But now, after some highs, lows and one reset (2011's X-Men: First Class), there are signs of wear and tear on a franchise that has grossed more than $4 billion.

Apocalypse, directed by Bryan Singer, earned $544 million worldwide, a sharp drop from the $748 million made by previous entry X-Men: Days of Future Past. What's more, stars Jennifer Lawrence, Michael Fassbender, James McAvoy and Nicholas Hoult have come to the end of their three-picture contracts. If new studio chairman Stacey Snider wants them to return, they won't come cheap.

"You're gauged by the success of the franchise," says box-office analyst Paul Degarabedian. "This one didn't engender the love of previous movies. It's time to go back to the drawing board."

There are other signs of paint chipping as well. Fox's solidly performing Wolverine spinoff series winds down with Logan (March 3), which is meant to be the last of the Hugh Jackman-fronted movies. (The movie just released a trailer which insiders say was the most watched spot in the history of the X-Men franchise.) In addition, Gambit, a solo spinoff movie to star Channing Tatum, failed to start production this year as planned and in August lost its director, Doug Liman.

And in perhaps the most unexpected development, Deadpool director Tim Miller pulled out of the sequel Oct. 22 after feuding with star Ryan Reynolds. (His composer Tom Holkenborg soon followed.) Deadpool was a surprise massive hit ($782.6 million) in February, so the studio has moved quickly to fill the sequel's director chair, with John Wick's David Leitch now in negotiations. And in a sign of how much faith it has in the Reynolds-starring franchise, Fox already is planning Deadpool 3, readying a filmmaker search for a storyline that will involve another X-team, X-Force, say sources.

Elsewhere, the reset button has been pressed. Sources say the flagship series will be reconfigured, with Simon Kinberg, overseer of the franchise as producer and writer, working on a new script. Singer, who directed four X-Men movies, will not be returning, according to insiders, but the script is being written with Lawrence, Fassbender and McAvoy optimistically in mind.

And after being on hold as Tatum shot Steven Soderbergh’s Logan Lucky, Gambit should move back into active development with a new filmmaker.

One of Fox's best hopes may be The New Mutants, a spinoff featuring superpowered teens with some overlap with the flagship X-Men. According to sources, director Josh Boone (The Fault in Our Stars) could even begin rolling cameras by spring.