A reckless combination of period piece, war drama, broad comedy, psychedelic fever dream, and occult horror-scape, Ben Wheatley's A Field in England doesn't have a true plot so much as an incidental setup. Taking place exclusively in a stretch of war-ravaged countryside during the English Civil War, the story follows a small group of cowardly soldiers fleeing battle and who find themselves trapped in the titular field with a terrifying maybe-sorcerer named O'Neill (Michael Smiley) and a cache of—what else?—magic mushrooms. O'Neill engages in a battle of wills with Whitehead (Reece Shearsmith), something of a de facto leader of this band of deserters, who also has vague connections to the mystical via his position as an astrologist's assistant. O'Neill's belief that there's treasure buried somewhere in the field, and that Whitehead is the key to finding it, triggers a series of diabolical power trips, torture sessions, manipulations, and killings that defy logic or conventional narrative structure, giving the film a genuinely hallucinatory quality; there's absolutely no way to predict what will happen next in this foggy, feral purgatory.
Thus, the film's main achievement is its tone. Consistently oblique and off-balance, it thrives on tensions both thematic and stylistic. The actors speak in an old English dialect appropriate for the setting, but their sentiments are crude and inflected with modern swear words. And while the stakes of O'Neill and Whitehead's power struggle, however nebulously articulated, certainly feel metaphysical or even divine, they're also usually bracketed by side players' jokes about venereal diseases or fecal matter. A Field In England is most successful when it lets these tensions manifest themselves organically; when it pushes too far in one direction or the other, often when it's trying to add humor to the proceedings, it treads too close to gimmick.
Field of England reaches its climax in a 10-minute-long tour de force of psychedelia, in which faces, bodies, and billowing cloaks swell and merge, eating each other and folding into their surrounding landscape at seizure-inducing speeds. The sensory and emotional cohesion of this sequence supersedes the need for any real explanation of the film's story—though a quiet but also brilliant denouement provides something akin to resolution. The terrible beauty of this climactic episode highlights what works best about Wheatley's vision: the sinister interplay between the occult and mundane, corporeal, and intuitive, even old and new. The result is a language of gestures, shapes, and movements that feels coherent and singular, and works as a productive tool for reinvigorating classic tropes (folk horror, war narrative, religious parable) with fresh energy.