'X-Men: Days of Future Past': Patrick Stewart and Ian McKellen return as Xavier and Magneto

Bryan Singer's return to directing on the "X-Men" movie series will include at least two actors from his previous "X" films: Ian McKellen and Patrick Stewart.

Singer, who's directing "X-Men: Days of Future Past," announced Tuesday (Nov. 27) via Twitter that McKellen and Stewart would be returning to their roles as Magneto and Prof. Xavier. Their younger counterparts from "X-Men: First Class," Michael Fassbender and James McAvoy, will also be in the cast, along with "First Class" stars Jennifer Lawrence (Mystique) and Nicholas Hoult (Beast).

That seems to confirm that the movie will hew pretty closely to the story of the early-'80s comics that give the movie its title. The story alternates between the present and a future in which mutants are confined to internment camps, allowing for both versions of Prof. X and Magneto to appear on screen.

Considering that "X-Men: First Class" was set in the early 1960s, the sequel would likely take place a short time after that, with McKellen and Stewart appearing in scenes set in a nightmare version of the early 21st century.

"X-Men: Days of Future Past" is currently set for release on July 18, 2014 -- the same day as the third "Hobbit" movie, which also stars McKellen.