Gary Oldman spent 200 hours in make-up to become Winston Churchill

The actor is playing the British Prime Minister in new Joe Wright film Darkest Hour

(AFP/Getty Images)

Gary Oldman has shown even more dedication to the acting cause than even he thought possible with his new Winston Churchill biopic.

The British actor was speaking at Focus Features' slate presentation when he revealed that it took over 200 hours in the make-up chair to be transformed into the former British Prime Minister for new Joe Wright's film Darkest Hour.

His hard work seems to have paid off: Oldman is unrecognisable in the film which takes place over the first five weeks of Churchill's tenure as PM when Hitler began invading.

Gary Oldman as Sir Winston Churchill in 'Darkest Hour'

Character actor Oldman, who has famously changed his appearance for many roles in the past (True Romance, The Fifth Element), considers Churchill to be a bit tougher than the rest.

He said: “They’re all challenging in their own way but Winston was kind of a hard one. It’s a lot to wrap your arms around. Not only the physical, but he is arguably the greatest Brit who ever lived… a kind of iconic figure. It was daunting but once I started to find out who the man was, it was… well, I never enjoyed anything so much in my life."

Wright's previous credits include Atonement, Hanna, Anna Karenina and Black Mirror episode 'Nosedive.'

Darkest Hour, which co-stars Lily James, Ben Mendelsohn and Kristin Scott Thomas, will be released in the UK on 29 December.