Three new cast members have been announced for Neil Marshall's upcoming Hellboy reboot. According to Deadline, Sophie Okenodo (Hotel Rwanda), Brian Gleeson (Assassin's Creed) and Alistair Petrie (Rogue One) have all signed on to the film that looks to reboot Mike Mignola's graphic novel series for the big screen.

The three newcomers join a cast that already includes David Harbour (Stranger Things) in the title role, Milla Jovovich (Resident Evil) as Nimue the Blood Queen and Ian McShane (American Gods) as Trevor Bruttenholm. The reboot was scripted by Mignola, Andrew Cosby, Christopher Golden and Aron Coleite. Two-time Game of Thrones director Neil Marshall is set to direct.

RELATED: Hellboy Reboot Has New Title

Okenodo has been cast to play the role of Osiris Club resident seer Lady Hatton, while Brian Gleeson is set to play the wizard Merlin. Alistair Petrie has been cast to play the role of Lord Adam Glaren, a high ranking member of the Osiris club.

The plot is rumoured to follow Hellboy as he squares off against a medieval sorceress, the Blood Queen, who seeks to destroy all of humankind. Mignola's involvement is said to have been minimal throughout the writing process.

RELATED: David Harbour Is The Hellboy We Need Right Now

Hellboy first appeared in San Diego Comic-Con Comics #2 in August of 1993. Since then he has appeared on the big screen on two occasions: 2004's Hellboy and 2008's Hellboy: The Golden Army, both directed by Guillermo Del Toro. Ron Perlman played Hellboy.

Hellboy is a half-demon who was summoned to Earth from Hell as a baby by Nazi occultists. Discovered by Allied forces, he was adopted by Trevor Bruttenholm. Hellboy works for the Bureau for Paranormal Research and Defense (B.P.R.D.) fighting against dark forces.