Suddenly, "Avada Kedavra" is not the most rancorous thing that could escape Harry Potter emblem Daniel Radcliffe's mouth.

In the upcoming Imperium, Radcliffe plays an FBI agent named Nate Foster who goes undercover with a white supremacist groupExpectedly, the movie includes a whole host of venomous, racist slurs, and in an interview with Trevor Noah on The Daily Show last night (August 15), Radcliffe said he couldn't apologize to his co-stars of color quickly enough when scenes ended.

"I did find myself — whenever I was using racial slurs and stuff in the film — I would have to go up to the actors afterwards and be like 'I'm so sorry,'" he recalled. "'I just, like, have to say it. I know you know that I don't mean this, but I still feel like I have to say it.' We were the most apologetic bunch of skinheads."

Radcliffe added that filming Imperium was a very strange dichotomy of beautiful movie-making and uncovering disturbing truths about American society.

"It was a very weird film to make in the one way because it was a fantastic experience and it was a great crew," he said. "On the other hand, we are dealing with this very heavy stuff and filming, like, right-wing, white-supremacist rally scenes and we were all wearing T-shirts that said 'white power' on them and stuff like that is weird and horrible."

Still, there was scene that Radcliffe said offered him a strange relief: the chronicling of his going totally bald.

"I had to shave my head which was on camera and I was happy to find out I don't have a strangely shaped or marked head in any way," he said.

Imperium hits theaters on August 19.

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