This is extraordinary: a seamless fusion of performance, direction, technical elements and text that is as magical as it is hard-hitting, and as life-affirming as it is depressing. You may not always completely grasp what is happening in this intense, compelling 75 minutes but I guarantee you won't be able to tune out.

Manfred Karge (described not inaccurately as "the Brandenburg Beckett" by critics, although I would opine that this work, at least, is rather more accessible than much of Beckett's) created a solo piece – first performed in the early '80s in his native Germany and premiered in the UK in '87 with Tilda Swinton – that is open to a wide degree of interpretation (the text contains not a single stage direction).

What it definitely is about is a woman who, for financial reasons, assumes the identity of her prematurely deceased husband, then lives for decades as a man throughout a particularly repugnant era of German history, through to a less regrettable period where he/she is forced to re-evaluate what has been endured and whether it was worth it. That is moving in itself, but watching it in 2017 with American and British mainstream politics apparently hurtling towards a moral abyss it feels worryingly urgent.

Alexandra Wood's elegantly spiky 'version' has the great virtue of not sounding like a translation: had it not been specifically German in terms of place and character names, and history, this would read convincingly as a new English language text, and a fine one at that. It is concise, witty, quietly moving, occasionally impenetrable and frequently enjoyably wayward. It recalls TS Eliot's The Waste Land with its elegantly jagged tapestry of distressed but imperative voices.

Although it is set to tour nationally and then over to New York, it is hard to imagine Bruce Guthrie and Scott Graham's enthralling production fitting as beautifully anywhere else as it does into Wiltons. Richard Kent's deceptively simple set – which initially appears to be a set of slats, a window, and some old furniture but turns out to be so much more complex – feels like an extension of this exquisitely ramshackle auditorium.

Rick Fisher's lighting, Mike Walker's sound design and, perhaps most of all, Andrzej's Goulding's jaw-droppingly inventive projections combine to create a world that feels simultaneously relatable, weird, eerie and absurd: a waking dream. Binding all of this together is a clear-eyed vision by the directors that is as enchanting (the rough magic elements such as when the hero/heroine unexpectedly exits the stage by diving into a suitcase, or dances with a jacket to simulate a human partner) as it is chilling (at one point the lead character dons a swastika armband in an attempt to make peace with the status quo, and it feels truly horrible): this is very exciting theatre.

Ultimately though, despite much visual evidence to the contrary including a mewling newborn and row upon row of downtrodden industrial workers (Goulding's amazing projections again), this is a one person show. None of it would properly land without a fully realised central performance and here Guthrie and Graham have struck gold with Maggie Bain. A human shapeshifter, Bain moves between the different ages and stages of the principal character's life, plus other figures in the narrative, with an ease and specificity that is exhilarating even as she breaks your heart. Physically (to say that she climbs the walls is no exaggeration), vocally and emotionally this is a beast of a role and Bain rises to the challenges magnificently. It's a tour de force: she will haunt you long after the performance is over.

Pieces of theatre that engage the mind, heart and soul as much as this one does are pretty rare. It's beautiful, endlessly inventive and it's also terrifying. You should see it.

Man to Man runs at Wilton's Music Hall until 23 September and then tours.