So meta: Watch Patrick Stewart watch James McAvoy as he finally shaves his head for ‘X-Men’

James McAvoy has accepted the inevitable: He has morphed into the final form of X-Men character Professor Charles Francis Xavier, while the original Xavier — Sir Patrick Stewart — watched gleefully from the phone.

When the X-Men movie series started, lovable lobster Stewart was cast in the crucial role of Professor X, leader of the X-Men and Dean of Xavier’s school for gifted Youngsters. The professor is known in the comics for his impressive telekinesis skills, a steady hand (usually pointed at his temple) and his lack of hair — a trait that Stewart mimicked in the first couple of films .

However, when McAvoy took over the role of Professor X in the origin story, set in the swinging ‘60s — way before he was head of anything — young Charles still had hair. The McAvoy films would constantly foreshadow the joke about Xavier’s soon-to-be-eradicated locks, and now in “X-Men: Apocalypse,� McAvoy is finally ready to make the jump.

So current “X-Men� director Bryan Singer called Stewart and captured the moment on FaceTime, connecting the professors. “Why don’t you save locks of it and send it to me,� Stewart joked. Honestly, we hope they did.

This shave has been a long time coming, and it should be remembered in mutant cinematic history with a hair plaque or something, right up there next to Rogue’s face-framing streaks.