Injecting a dose of mystery into the long holiday weekend, Fox has staked out dates for six untitled Marvel films.

These are in addition to the already-announced 2018 lineup featuring The New Mutants (April 13), Deadpool 2 (June 1) and X-Men: Dark Phoenix (Nov. 2). The new date are June 7 and Nov. 22 in 2019; March 13, June 26 and Oct. 2 in 2020; and March 5 in 2021.

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Fox of course controls the film rights to the Fantastic Four and the enormous stable of X-Men family of characters, opening up a lot of potential candidates to fill these slots. Sequels to The New Mutants, Deadpool and X-Men are the most obvious contenders, with X-Force following close behind, as Deadpool 2 introduces Cable and Domino, laying the foundation for that team.

We also can't forget Gambit, which has experienced repeated delays, losing director Doug Liman and its place on the Fox calendar in the process; still, the studio and actor Channing Tatum appear committed to the project.

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That brings us to the most vexing of its Marvel properties, the Fantastic Four. Fox's third and most recent attempt to adapt the comic, the 2015 reboot directed by Josh Trank, was a critical and commercial failure, but producers remain interested in the property. The studio can only retain the rights if a Fantastic Four film is in development within a period prescribed by the agreement with Marvel (you'll recall the hand-wringing about Daredevil and Ghost Rider before those rights reverted to Marvel), so another run at the franchise in 2020 or 2021 is a distinct possibility.

(via ComingSoon)