Ahh, post-production, that magical time when a director can use computers and good old-fashioned ingenuity to fix the hundred little things that went wrong while shooting. Flubbed lines can be re-recorded and spliced in, flawed shots can be surgically removed, and inconsistencies in continuity can be digitally erased from the frame. That last one has become something of a major concern for the Justice League production as it winds down, because the process of reshooting has dealt director Joss Whedon one hairy, noticeable continuity error.

Unless something is done, observant Justice League viewers will note that Superman star Henry Cavill appears to gain and lose a mustache several times over the course of the upcoming superhero crossover film. Cavill came to set for reshoots sporting a lustrous, robust ’stache that he is contractually forbidden from shaving for the concurrent Mission Impossible 6 shoot, creating a problem, as audiences are not used to Superman looking like John Holmes’ more strait-laced brother. Whedon turned to his post-production effects wizards to magick the offending hairs off of Cavill’s upper lip, and a new interview with Business Insider has revealed just how much work it’ll take to essentially shave the actor’s face using a computer. Consider the following quote from VFX expert Dave Fleet:

If we were to remove a beard we would have to digitally re-build the actor’s face behind the hair mass. We would need to build a 3D model of the face and then shade the surface of the skin to look realistic. We would then need to track the 3D model to the movement of his head and potentially re-animate his mouth. The amount of lip animation would depend on how much of the original beard occluded his lips. We would need to paint out the parts of the beard that extend beyond his shaven face.

In a final analysis, Fleet gauges the amount of work it’d take to de-moustachify Cavill for a one-minute clip at six weeks, and a staggering 25 weeks for a measly five-minute clip. The film’s release is not that far off, slated for November 17 — how much fun would it be if editors were working day and night, right down to the wire, all to carefully remove each and every mustache hair from a double-booked Superman?

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