Watch: Daniel Kaluuya discusses his role in Judas and the Black Messiah
Daniel Kaluuya says it was a "real challenge" to embody the late Black Panther Party figurehead Fred Hampton in Judas and the Black Messiah.
The 32-year-old Brit portrays Hampton in Shaka King's movie, which focuses on the civil rights activist in the months leading up to his death in 1969, as well as the actions of FBI informant William O'Neal — the "Judas" to Hampton's "Messiah".
Kaluuya tells Yahoo Entertainment UK that portraying a real person — for the first time since 2008's Cass — requires a different set of tools for an actor.
"It was a real challenge and something to get my head around," he says. "The boundaries have already been created and your target is smaller."
He adds: "When it's a fictional character, you create the boundaries and then you can do this and do that. You need boundaries, but you do that in order to build the full life.
"The real shift is when I started seeing that it's not a boundary, it's a guide. They're guides in order to say 'go this way, go that way' or 'don't go this way, don't go that way'.
"Instead of me having to do it, the man was doing it for me and the truth was doing it for me."
Kaluuya, who has already won a Golden Globe and a Critics Choice Award for his performance, says the most difficult element of the job was "getting my head around the fact it's not an impersonation, it's an interpretation".
The actor embodies Hampton's physicality in the movie, bulking up considerably for the role, and adopts a distinctive accent to portray the Illinois-born activist.
"If I got the exact kind of voice, sometimes it would not be serving the story or serving the piece and it won't resonate because it's not in me," says Kaluuya.
"I had to get my head around being clear and informing why I'm choosing the interpretation that I'm choosing and then imbuing that with confidence and belief and just committing to it with conviction and moving for that.
"Getting to that place was a challenge."
Judas and the Black Messiah's take on Hampton is one of two to play a part in this year's awards season, with Kelvin Harrison Jr. — who Kaluuya describes as a "fantastic talent" — portraying him in a small role as part of Aaron Sorkin's The Trial of the Chicago 7.
As far as awards attention goes, though, Kaluuya — who was also a contender for his breakout turn in Get Out — is not focused on glittering trophies.
He says: "I just want the film to reach the people that pay. I want them to connect to it and to hear his words and hear about the Black Panther Party.
"That for me is the North Star in this particular process."
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As well as Kaluuya and Stanfield, the film also stars Dominique Fishback as Hampton's girlfriend Deborah Johnson, Jesse Plemons as O'Neal's FBI handler and Martin Sheen under heavy prosthetics as bureau boss J. Edgar Hoover.
Judas and the Black Messiah will be released on VOD platforms from 11 March.
Watch: Trailer for Judas and the Black Messiah