Onslaught does not build its ensemble around a mystery hero. Adria Arjona’s Celeste is clearly the centre: an Army sniper and mother whose survival skills become the only barrier between her daughter and escaped super soldiers. The useful cast question is how everyone else fits around that protection mission.
Cast at a glance
| Actor | Character or role | Status |
|---|---|---|
| Adria Arjona | Celeste | Army sniper and central protagonist |
| Blake Kennedy | Daisy | Celeste’s young daughter |
| Alex Pereira | The Butcher | Major physical threat |
| Dan Stevens | Dr Hans Kammler | Named principal character |
| Rebecca Hall | Hanna Kammler | Named principal character |
| Eric Wareheim | Kovacks | Named ensemble character |
| Reginald VelJohnson | Josiah | Named ensemble character |
| Michael Biehn | Baylor | Named ensemble character |
| Drew Starkey | Cyrus | Named ensemble character |
| Maurice Greene | Teddy | Named ensemble character |
| Jacob Scipio | Griffin | Named ensemble character |
Adria Arjona as Celeste
Celeste is the person who turns Onslaught from a military-experiment story into a survival film. She is an Army sniper living with her daughter in the desert, so the escaped soldiers are not an abstract national-security problem. They arrive at her home and place Daisy directly in danger.
That combination of professional skill and maternal urgency defines Arjona’s role. Celeste can use a rifle, read a threat and fight back, but she cannot approach the attack like a clean mission. Every tactical choice also has to keep her daughter alive.
Blake Kennedy as Daisy
Daisy is Celeste’s young daughter and the emotional stake of the film. She is not simply someone waiting to be rescued: her presence changes the geometry of every escape. Celeste has to create distance from the attackers without losing contact with the person she is protecting.
The mother-daughter relationship is therefore the clearest line through the ensemble. Military history explains why Celeste can resist the attack; Daisy explains why she refuses to run alone.
Alex Pereira as the Butcher
The Butcher gives the rogue-soldier threat a recognisable face. Pereira’s combat background makes the casting immediately physical, but the character matters because he pushes Celeste into a fight where ordinary training may no longer set the limit.
This is the cast guide’s central conflict: a sniper who understands human opponents against a pursuer designed to exceed them. The film can add laboratories, conspiracies and supporting players around that clash, but Celeste versus the Butcher is the cleanest expression of its danger.
Dan Stevens as Dr Hans Kammler
Dan Stevens plays Dr Hans Kammler, one of the named principal characters around the super-soldier crisis. The professional title places him on the scientific side of the movie’s character map, although A24’s public synopsis does not spell out his allegiance or the extent of his responsibility.
That uncertainty is worth preserving. Hans may help explain how the soldiers were created or why they escaped, but assigning him a heroic or villainous function before the film establishes it would flatten a role the marketing is keeping guarded.
Rebecca Hall as Hanna Kammler
Rebecca Hall plays Hanna Kammler. She shares a surname with Hans, making the Kammler pair an obvious point of connection inside the ensemble, but their exact relationship should not be guessed from the name alone.
Hanna also gives the cast a second major figure outside Celeste’s immediate mother-daughter line. How the Kammlers connect to the experiment is one of the role questions the film itself needs to answer.
Eric Wareheim, Reginald VelJohnson and Michael Biehn
Eric Wareheim appears as Kovacks, Reginald VelJohnson as Josiah and Michael Biehn as Baylor. Their character names are disclosed, but the public synopsis does not assign them a clear place in Celeste’s family, the military project or the escaped squad.
That makes them supporting pivots rather than empty cast-list entries. Once their loyalties are revealed, they can widen the film beyond a straight chase by showing who knew about the project, who is trying to contain it and who is caught in the desert with Celeste.
Drew Starkey, Maurice Greene and Jacob Scipio
Drew Starkey plays Cyrus, Maurice Greene plays Teddy and Jacob Scipio plays Griffin. The names are public, but their relationships and alignments remain under wraps. That distinction matters because an action ensemble can easily be mislabelled as allies, soldiers or victims before the story identifies them.
For now, the reliable cast map has Celeste and Daisy on one side, the Butcher as the most visible threat, and the Kammler thread positioned near the science behind the crisis. Kovacks, Josiah, Baylor, Cyrus, Teddy and Griffin fill out the human network whose loyalties the film has not fully disclosed.
Need the cinema date, runtime and India availability caveat? Read our Onslaught theatrical release guide.
Deciding whether to watch? Our Onslaught review explains why Adria Arjona carries the film even when the siege takes too long to arrive.
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