Paul Giamatti will portray the tyrant King John in Ironclad, joining James Purefoy in the medieval-era action that Jonathan English is directing.

According to Variety, the drama is scripted by Erick Kastel and English, and pits a member of the formidable Knights Templar (Purefoy) and his "Magnificent Seven" cohorts who defend Rochester Castle against King John and his army in 13th century England.

Production begins in Wales next month.