However, the filming schedules have since overlapped, and Henry has had to reprise his role as Superman while sporting his new mustache, which he has allegedly been banned from shaving while working on the Mission: Impossible sequel, according to Variety.com.
The grooming predicament means Justice League filmmakers will have to spend extra time and money carefully removing the hair from Cavill's upper lip in post-production on the Warner Bros. blockbuster.
Cavill isn't the only cast member having to dash back and forth between movies - Ezra Miller, who portrays Barry Allen and his superhero alter ego The Flash, has also had to fit the reshoots around his schedule for Fantastic Beasts and Where to Find Them 2.
Studio officials determined additional filming was required for Justice League following Zack Snyder's departure as director in May (17) after the death of his daughter.
Joss Whedon was brought on board to complete the Batman v. Superman: Dawn of Justice moviemaker's project, but insiders tell Variety he will not be given a directing credit, and is instead likely to be added as a producer or screenwriter after helping to "punch up the dialogue" during reshoots, which is reportedly costing an estimated $25 million .
Justice League, which also stars Ben Affleck as Batman and Gal Gadot as Wonder Woman, is still scheduled to hit cinemas in November (17).