Portraying one of the leading Nazis and architects of the Holocaust comes with all sorts of challenges, responsibilities and concerns for actors. Just ask Martin Müller, the German actor who plays SS leader Heinrich Himmler, known as the chief implementer of the Nazis’ so-called “Final Solution,” in writer-director Felix Randau‘s I Is Another (Ich Ist ein Anderer), which world premieres on Friday, Aug. 7 in the Piazza Grande program of the 79^th edition of the Locarno Film Festival in Switzerland.

Set in 1952, the film stars Claes Bang as Felix Kersten, the former massage therapist to Himmler, who gets ambushed by journalist Hedda (Valerie Pachner). Kersten claims to have helped thousands of concentration camp prisoners to freedom during the Nazi era by using his influence with Himmler, but Hedda has her doubts and wants to prove he is making himself look like a hero that he really isn’t.

Casting the role of Himmler proved to be the production’s toughest challenge. “The only part that was really hard to cast was Himmler,” Randau tells THR. “I was looking for someone who could play a weasel kind of guy, but it was really, really tough.” He asked some actors about the role and got a less-than-enthusiastic reception. “They accused me of providing a stage for an evil guy like Himmler. I think that is really ridiculous and a big mistake because evil is a part of creation. If you ignore or neglect it, it will grow in the dark, and that’s what’s happening here in Germany, as we can all see.”

That warning doesn’t come out of nowhere: the Alternative for Germany (AfD) party has been on the rise in the country, becoming a far-right force to be reckoned with in an age of rising anti-immigration sentiment, economic worries and traditional party fatigue. In Germany’s 2025 federal election, the AfD came in second and has developed strongholds in the country’s Eastern states of the former GDR.

Against that backdrop, Randau and his casting director, Suse Marquardt, cast their net far and wide, eventually landing on a talent best known for stage and TV work. “I’m really happy that we found Martin Müller,” Randau tells THR, lauding him for bringing to the role just what he was looking for and more.

Müller joins an illustrious list of actors who have portrayed Himmler on screen. They include Stephen Graham, who played the Nazi in the war drama The Man With the Iron Heart (2017), Eddie Marsan, who featured as Himmler in the historical drama The Exception (2016), Matthias Freihof, who was Himmler in the Tom Cruise starrer Valkyrie (2008), Kenneth Tigar, who took on the role in the alternate-history series The Man in the High Castle (2016–2019), Ulrich Noethen, who portrayed Himmler in both the Academy Award-nominated Downfall (2004) and in My Führer – The Really Truest Truth About Adolf Hitler (2007), as well as Ian Holm, who stepped into the Nazi’s boots for the miniseries Holocaust (1978).

For Müller, the role came through a longstanding connection with Marquardt. “I got an e-mail for an e-casting, and I did it with my coach and sent it to Suse, and she said, ‘the director wants to meet you’,” he recalls. “And Felix came to Munich, where I live, instead of me going to Berlin. We just met in a restaurant, and after two hours of talking, I asked him how many people he was meeting. And he said, ‘I’m fine with you. I just wanted to meet you.’ So I was very happy.”

Landing the part came with its own reckoning, though, given the horrific things Himmler was responsible for. “It’s horrible to take on that role on the one hand, but on the other hand, it’s an interesting person,” Müller says. “He is a horrible person, but people who are a horror are always interesting for an actor. For this part, Himmler isn’t in action in concentration camps or anything like that. So, the film doesn’t show the real horror of Heinrich Himmler because it’s told via Felix Kersten. And he doesn’t tell us about all the horrors because he doesn’t want to be seen in a bad light.”

Even so, some scenes were particularly hard to shoot, both emotionally and psychologically. “Claes and I had this scene where we had to discuss how many Jewish people we could save,” Müller shares. “We filmed this scene the whole night, and at the end, we said to each other that it was so disgusting to talk about numbers, like people were nothing. Himmler had no empathy and was really cold. In his mind, he was just organizing things. People talk about Heinrich Himmler as someone who saw himself as a mathematician of the Holocaust. For him, there were no human beings behind the numbers.”

The role stayed with him well after filming wrapped. “It was really difficult to leave the character,” Müller recalls. “It was one thing to leave the four or five kilos that I had gained for the role behind. That was also very hard, and I just finished doing that. But the other thing was leaving this ugly character. These things just really stick with me. I just kept thinking, ‘what are politicians doing nowadays? Oh my God!’ For me, it’s a horror what the politicians are doing at the moment.”

That physical transformation started with a simple request: “Felix asked me, ‘Could you be a bit more round in the face?’ So, I did less sport and ate more to gain four or five kilos.”

As for research, Müller deliberately skipped studying other actors’ takes on the role. “I think he was a totally uninteresting person,” he says. “There aren’t any films or other [material] with private stuff about him. He was just hiding. With Hitler, Goebbels or Göring, we know a lot of private stuff. We have some speeches by Himmler, but we have no private recordings to know how he was talking when not giving a speech. So I just didn’t care about that but tried to do it my way. And keep in mind: It’s not the ‘true’ Heinrich Himmler in the film. It’s Heinrich Himmler as [told] by Kersten. And you don’t know what is true or wrong. That’s what the whole film is actually about.”