Kathryn Bigelow didn't make 'Detroit' for ''entertainment'' purposes.

The 65-year-old filmmaker felt a huge ''responsibility'' to stay faithful to the story of the 1960s race riots in the US city and wanted to create a ''dramatisation of true events'' in order to educate and inform her audience.

Speaking at a press conference for the film at London hotel Claridge's on Wednesday (16.08.17), Bigelow said: ''I suppose I never thought about it as entertainment but rather as a dramatisation of true events.

''There was very little knowledge about what happened outside of Detroit. I had no knowledge of it myself.

''The script for a large part was partly formed from court documents and testimonies of people there at the time.

''We felt a responsibility to stay as faithful to the research as we can. I think we were all steep in archive footage that really dictated the look and feel of the film.''

'Detroit' follows the lives of black and white people during the 1960s riots and focuses on the murder of three black men in the Algiers Motel.

Many of the characters featured in the film are based on real people, including Melvin Dismukes (John Boyega) and Julie Hysell (Hannah Murray) and Bigelow revealed she met with them and credits them with being ''hugely responsible'' for the way the movie developed.

She said: ''John and Hannah's characters were actually people that we met with. Julie was on the set every day.

''They were hugely responsible for how the story unfolded.''

Will Poulter, who stars as violent police officer Krauss, said the script was ''incredibly well researched'' but they had to ''dramatise'' some events due to contaminated or lost evidence.

He said: ''The script was incredibly well researched. Historical accuracy inherent in the writing.

''We wanted to give the upmost respect for accuracy and the truth. Of course, we had to dramatise where there aren't the facts.

''Some of the evidence had been contaminated or lost. There was an emphasis shining light on the truth. A lot of the research was done for us.''