Why did filmmakers have to CGI Henry Cavill’s mouth in Justice League?

Filmmakers had to use CGI to alter Henry Cavill’s mouth in Justice League because of his contractual obligations to another movie, Mission: Impossible – Fallout. Specifically, the issue was that Cavill had grown a mustache for his role in that film, and when Justice League re-shoots were scheduled, he was contractually obligated to keep the mustache for the duration of filming for Mission: Impossible – Fallout.

Director Joss Whedon had to oversee re-shoots of certain scenes in Justice League after original director Zack Snyder stepped down from the project. During these re-shoots, Henry Cavill was called back to film additional scenes as Superman. However, since he still had the mustache, the decision was made to use CGI to edit out the facial hair and create the illusion that he had a clean-shaven face.

The use of CGI to edit out the mustache proved to be a costly and time-consuming process. The effect was not completely convincing, with many viewers criticizing the look of Superman’s face in certain scenes. Nevertheless, the filmmakers felt that it was necessary to keep the continuity of the film and ensure that the character of Superman looked the way that audiences expected him to.

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