Dan Stevens Says His ‘Onslaught’ Villain Draws Directly From the Real-Life Operation Paperclip

Adam Wingard has built a distinct reputation within genre filmmaking for grounding his most outlandish concepts in scraps of real history, using conspiracy theories and declassified programs as launching pads for pulpy, blood-soaked storytelling. His latest collaboration with longtime creative partner Dan Stevens continues that tradition, weaving a decades-old government secret directly into the DNA of its central villain.

That villain marks a significant departure from the role that first made Stevens and Wingard’s partnership so memorable. Back in 2014, Stevens played David Collins, an unhinged government-engineered super soldier, in Wingard’s cult favorite ‘The Guest.’ Rather than reprising that character for a direct sequel, Stevens instead plays the scientist responsible for creating an entirely new generation of those same genetically engineered killers.

That character is Dr. Hans Kammler, and Stevens has confirmed his backstory draws directly from Operation Paperclip, the real-life secret intelligence program that brought Nazi scientists into the United States following World War II. Stevens described Kammler as descended from that legacy, calling him “a deranged Nazi scientist” whose presence in the film’s shadowy defense contractor plotline ties directly into the broader conspiracy-laced mythology Wingard has built across his recent work.

Speaking about how deeply that history informs the character, Stevens explained that Kammler represents a core piece of the fictional universe Wingard set out to construct. That universe now spans three films, beginning with 2011’s ‘You’re Next,’ continuing through ‘The Guest,’ and culminating in ‘Onslaught,’ which Wingard has described as completing a loose spiritual trilogy tied together by recurring themes around shadowy government experimentation.

The name Hans Kammler isn’t fictional invention either. Wingard has explained that the character is directly named after a real SS general who oversaw construction at Auschwitz and ran the brutal V-2 rocket slave labor program at Mittelbau-Dora, where roughly 10,000 people died during the war. That grim historical backdrop gives the film’s over-the-top genre thrills an unusually dark real-world foundation.

Wingard has said his interest in the post-World War II era, particularly Operation Paperclip, shaped much of the film’s underlying conspiracy, framing it around a provocative question: if the United States was willing to recruit and later suppress the record of someone like rocket scientist Wernher von Braun in exchange for his technical expertise, what similar programs might the government have run entirely in secret. That thematic through line gives ‘Onslaught’ a layer of historical unease beneath its splashy genre violence.

Stevens has said the character was written specifically with him in mind, given his fluency in German from prior roles. Wingard has confirmed as much, explaining that the team wanted an “evil third-generation Paperclip Nazi character” and tailored the role knowing Stevens could authentically deliver both the accent and the theatrical menace the part demanded.

Stevens’ casting also continues his ongoing creative partnership with Wingard, having previously worked together on ‘Godzilla x Kong: The New Empire’ in addition to ‘The Guest.’ That history gave Stevens confidence in signing on for ‘Onslaught’ even before fully understanding the shape the project would take, describing his excitement simply at the prospect of collaborating with Wingard and writer Simon Barrett again.

The film also stars Adria Arjona as a former Army sniper defending her daughter against the genetically engineered soldiers Kammler helped create, alongside Rebecca Hall as Kammler’s domineering wife and handler. Michael Biehn, Drew Starkey, Reginald VelJohnson and UFC champion Alex Pereira round out the supporting cast.

‘Onslaught’ opened in theaters September 4 through A24, giving audiences a chance to see how deeply Wingard and Stevens have woven real historical conspiracy into their latest slice of genre mayhem. Given how much research and thematic intent went into building out Kammler’s backstory, the character looks poised to become one of the more memorable villains in Wingard’s growing body of work.

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