Fox is moving ahead with its fantasy movie “Superior,” bringing on the writing team of Brandon and Phillip Murphy to adapt Mark Millar’s comic book series, Variety has learned exclusively.

Tarquin Pack and Matthew Vaughn are producing “Superior,” in which an athletic 12-year-old boy is diagnosed with multiple sclerosis. To regain his strength, he’s granted one wish from an alien monkey — to become Superior, his favorite superhero. But things go awry when he learns that the monkey is a demon and that he must sell his soul to keep his powers.

The seven-issue “Superior” series, written by Millar and illustrated by Leinil Francis Yu, was published between 2010 and 2012 through Icon Comics, a creator-owned imprint from Marvel.

Three of Millar’s comic book series — “Wanted,” “Kick-Ass” and “Kingsman: The Secret Service” — have been adapted into feature films. Vaughn produced, directed and wrote “Kick-Ass” and “Kingsman,” and is writing the sequel to the latter.

Fox came on board “Superior” in 2014, several years after Vaughn had optioned the property.

Brandon and Phillip Murphy have been attached to Dimension’s horror project “Transference” and the Virgin Produced adaptation of Robert Greenfield’s book “Exile on Main Street: A Season in Hell With the Rolling Stones.” They are repped by WME and Mosaic.