Will Poulter relied on Kathryn Bigelow to help with his evil character in 'Detroit'.

The 24-year-old actor stars as Philip Krauss, a police officer involved in the Algiers Motel incident of 1967, in which three African American men were killed during the 12th Street Riot, and said he needed the filmmaker to help maintain a ''calm, level-headed'' feeling.

Speaking at the press conference for the film at London hotel Claridge's on Wednesday (16.08.17), Poulter said: ''I relied heavily on Kathryn.

''Someone who in the presence of chaotic and overwhelming action, maintains a calm, level-headed, aspiring closure.

''I think the fact that I was generally friends with the cast helped as well. We had those bonds and respect and trust with each other.

''A sense of purpose came with the film. The psychology of that character was very uncomfortable. Any time I was feeling emotional, I would think of those that who have been the recipient of that abuse.

''My feelings don't even measure up to what the real people went through. I kept that in mind when shooting the film.''

Oscar-winning filmmaker Bigelow, who has helmed very successful gritty movies including 'The Hurt Locker', recently revealed she based her script on court reports and testimonies of people who witnessed the atrocity.