"Monsters" star Scoot McNairy has been cast in an unknown role in "Batman v Superman: Dawn of Justice," Deadline reveals in a brief report guaranteed to ignite another found of fan speculation. Warner Bros. hasn't confirmed the news.

The 36-year-old actor, who appeared in Ben Affleck's "Argo" and can currently be seen in "The Rover" and on AMC's "Halt and Catch Fire," joins a confirmed cast that includes Henry Cavill as Superman, Affleck as Batman, Gal Gadot as Wonder Woman, Amy Adams as Lois Lane, Jesse Eisenberg as Lex Luthor, Jeremy Irons as Alfred, Laurence Fishburne as Perry White, Diane Lane as Martha Kent, and Holly Hunter.

With the Zack Snyder film expected to lay the groundwork for "Justice League," complete with cameos by Cyborg and Aquaman, speculation will undoubtedly drift toward McNairy playing a superhero. However, it seems just as likely that he's been cast in a non-costumed role.

Written by Chris Terrio and David S. Goyer, "Batman v Superman: Dawn of Justice" arrives May 6, 2016.