Ever since X-Men: Apocalypse hit theaters last summer, fans have been kept largely in the dark about 20th Century Fox's plans for continuing the main X-Men franchise. The studio has announced a number of spin-offs, such as The New Mutants, X-Force and Gambit, but there is practically nothing known about how the studio intends to continue the flagship series. One of the more persistent rumors is that the studio will reboot the Dark Phoenix story line, which was told over the original trilogy. While that still hasn't been confirmed, a new production listing may have the most damning evidence yet that the studio is rebooting the Dark Phoenix saga.

The Dark Phoenix saga was largely told through 2003's X-2: X-Men United and 2006's X-Men: The Last Stand. However, the events of 2014's X-Men: Days of Future Past essentially eliminated that entire timeline, creating a brand new timeline where Jean Grey (Famke Janssen) was still alive in present day. X-Men: First Class was set in the 1960s, with X-Men: Days of Future Past taking place in the 1970s (and parts of the movie are set in present day), while X-Men: Apocalypse closes out the trilogy in the 1980s. Producer Simon Kinberg had teased that the next X-Men movie was set in the 1990s, presumably with the cast members from the prequel trilogy. A production listing went up today at My Entertainment World for a new movie entitled X-Men: Supernova, which is scheduled to start production this May in Montreal, and which many believe is proof that the Dark Phoenix reboot is happening.

Last month, a report surfaced that claimed a new X-Men movie will start production this summer in Montreal, the same place where Bryan Singer directed X-Men: Days of Future Past and X-Men: Apocalypse. Michel Trudel of MELS Studios in Montreal confirmed that the production will film on two of their stages for several months, but it was never confirmed which project this may be. What's interesting is that the My Entertainment World listing for The New Mutants was updated yesterday, revealing that production will actually take place this coming April in Montreal. While it could be a simple mix-up, it could also mean that both of these movies will be essentially shot at the same time

Rumors surfaced in November that Bryan Singer will return to direct this new X-Men movie, but nothing was ever confirmed by the studio. As for who may actually star in this movie, it is believed that young stars such as Sophie Turner (Jean Grey) and Tye Sheridan (Cyclops) will return, but the entire cast from the prequels may not return. That report claimed that the contracts for stars Jennifer Lawrence, Michael Fassbender, Nicholas Hoult and James McAvoy expired after X-Men: Apocalypse. While it's certainly possible that the actors could renew thier contracts, it may cost the studio quite the pretty penny, since they're all so in demand these days.

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It's also worth noting that, back in May, director Bryan Singer revealed in an interview that he eventually wants to set an X-Men movie in outer space, which was another indication that the Dark Phoenix saga was ripe for a reboot. In the original trilogy, a number of story elements involving aliens and outer space were discarded, but now that the whole timeline has been reset, and the franchise is more popular than ever, perhaps the studio is interested in a more definitive and thorough adaptation of the Dark Phoenix story. While nothing is confirmed yet, hopefully 20th Century Fox will finally clear the air about what X-Men 7 really is.