Gary Oldman is a transformative actor – someone who embodies roles through performance and delivery, but also revels in the possibilities of Hollywood make-up, from his Oscar-winning turn as Winston Churchill in Darkest Hour, to the lavish costuming of Bram Stoker’s Dracula. But for Mank – David Fincher’s upcoming film about Herman J. Mankiewicz, the writer of Citizen Kane – the beloved British actor stepped away from those trappings to deliver a much more stripped-down performance.