New Zealand actor Callan Mulvey is heading into the biggest superhero clash in cinema history.

Mulvey, best known to Australian audiences as the star of TV series Rush and the crime dramas Underbelly and Bikie Wars: Brothers in Arms, is joining the highly anticipated Batman vs Superman film.

His role has not been announced, but it is understood he will play a new character created for the film rather than one lifted from the history of either superhero.

Mulvey, who also appears in the Marvel comics adaptation Captain America: The Winter Soldier, secured the role after filming 300: Rise of an Empire, directed by Zack Snyder. Snyder is also directing Batman vs. Superman, the big-screen clash of DC Comics' two most iconic superheroes.

The film will star Ben Affleck as Batman and Man of Steel star Henry Cavill as Superman.

When Affleck's casting was announced, it was met with an almost unprecedented fan backlash.

It will also star Israeli beauty queen and actress Gal Gadot as Wonder Woman, Jesse Eisenberg as Superman's legendary nemesis Lex Luthor and Jeremy Irons as Batman's loyal butler, Alfred Pennyworth.

The film was originally slated for a 2015 release but has since been delayed until May 2016.