WARNING: MILD "X-MEN: APOCALYPSE SPOILER AHEAD

The story of Professor X's hair loss in "X-Men: Apocalypse" is said to be different than in the comic books, prompting many to wonder what really happened to the wise professor. Well, James McAvoy recently shed light on the matter in a TV interview, according to Den of Geek.

Bryan Singer's highly-anticipated "X-Men Apocalypse" will be rounding off the trilogy that started "X-Men: First Class." As such, it will feature a hairless Professor X by the end of the film.

Acording to Cinema Blend, McAvoy revealed how Professor X lost all his hair in "X-Men: Apocalypse" during an appearance on "The Graham Norton Show" with Daniel Radcliffe to promote their new film "Victor Frankenstein."

"He ends up going through something so horrible and physically painful that he literally half pulls his hair out/half it falls out. Maybe, or maybe not...I just shit myself because I know Fox Studios who own me might be angry with me for sharing that," the 36-year-old British actor explained.

It turns out Professor X's hair loss won't be due to male pattern baldness of some sort, but will be from a severely traumatic event that will have the professor yanking some of his hair out.

The first time a bald Xavier was shown in the big screen was in "First Class," reportedly with several references to shaving and aging. However, with McAvoy's recent revelation, it would seem that it will be a less natural process for the stressed out professor.

In general, Charles Xavier has had a lot on his plate having to undergo his legs getting paralyzed at the end of "X-Men: First Class" as Magneto (Michael Fassbender) shot his spine with a bullet. Plus, Xavier also lost many students in the Vietnam War. He also had to give his powers up in "Days of Future Past."

Regardless, whatever makes Professor X lose all his hair will be the doing of the new villain Apocalypse in "X-Men: Apocalypse," and it would appear severely stressful that the Professor was prompted to pull his hair out.

In the comic books, Professor X's hair loss was due to an advancement of his mutation.

Check out McAvoy's explanation in the video below:

Meanwhile, the "X-Men: Apocalypse" trailer is expected in a couple of weeks.

Whatever really caused Professor X's hair loss will be revealed when the film is released on May 27, 2016.

Check out a report on Professor X's hair loss below.