The latest photo posted to Bryan Singer’s Instagram account doesn’t show you a whole lot, but it does tell you quite a bit. Not only will we be seeing Apocalypse in the next X-Men outing, but we’ll be getting another new character from the comic books as well — one who hasn’t appeared in any previous X-Men film: Caliban.

If you’re unfamiliar with the comics, you might be scratching your head at Singer’s latest set photo:

 

 

The director is filming a scene in Caliban’s underground lair, but who is Caliban, exactly? He’s an albino mutant with the power to track down other mutants (similar to Professor X’s Cerebro), which would make him pretty valuable to some of the more nefarious characters. Caliban is a member of the Morlocks, a group of mutants who choose to live underground, and in the comics, he was sought out by Apocalypse, who transformed him into one of the Four Horsemen.

The involvement of Caliban in X-Men: Apocalypse may also indicate a tie-in to Deadpool, which features a Morlock character of its own in Gina Carano’s Angel Dust. Something to think about.

X-Men: Apocalypse features Jennifer Lawrence, Michael Fassbender, James McAvoy, Nicholas Hoult and Evan Peters reprising their roles from previous films, alongside Rose Byrne, reprising her role as Moira McTaggert from First Class. New cast members include Sophie Turner as Jean Grey, Tye Sheridan as Scott Summers, Alexandra Shipp as Storm and Olivia Munn as Psylocke, along with Oscar Isaac as the titular villain, Apocalypse.

X-Men: Apocalypse arrives in theaters on May 27, 2016.

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