Dementia is a syndrome that brings with it a unique grief: the only kind that can be shared, for a time at least, between the mourned and their mourners, until the latter are left to it themselves, awaiting a second, more sudden, farewell. Its liminal nature — blurring conceptions of life and death, self and other — is what makes it so endlessly fascinating to filmmakers and actors alike, calling on a rich range of transitory emotions, though things can easily tip into glib, sudsy melodrama if written and played with too heavy a hand. British writer-director Harry Macqueen pitches it just right in his delicately heart-crushing sophomore feature “Supernova,” thanks in no small part to the ideally matched star duo of Colin Firth and Stanley Tucci: As a longtime couple figuring out how to live — or not — under dementia’s ever-encroaching shadow, their joint thespian grace and reserve take on an undertow of raging, disorganized despair.
World-premiering in competition at San Sebastián — a major coup for the Spanish fest, which tends to lose dibs on starry English-language titles to Venice and Toronto — “Supernova” is beguilingly modest by design: essentially a two-man chamber piece twisted into the winding form of a British road movie, where nothing can move too fast, lest we reach the shore too soon. It’s a virtual blockbuster, however, relative to actor-turned-filmmaker Macqueen’s shoestring 2014 debut “Hinterland,” the airy promise of which his follow-up confirms, and then some. Despite the film’s solemn smallness of scale, its leads — both in terrific form, with Firth in particular demonstrating new cracks and quivers in his stiff-upper-lip persona — should draw mature audiences in healthy numbers beyond the festival circuit. (Presumably with BAFTA season in mind, U.K. distributor Studiocanal currently has “Supernova” scheduled for a Nov. 27 release.)
As it follows sixtysomething partners Sam (Firth) and Tusker (Tucci) in a cluttered camper van through the north of England, on what looks to be their last vacation before Tusker’s health severely deteriorates, Macqueen’s talky original screenplay promises no surprises: There’s only one way their journey can go, and the film resolves to follow it as intimately as possible. “We’re not going back, you know,” Sam says to Tusker in the film’s very first line of dialogue — and while he means it in a banal domestic sense, as a last call for any forgotten items before they hit the open road, they and we can hear the searching, melancholic subtext of those words.
For Tusker, as it turns out, has quite deliberately left something behind: the medication that’s at least supposed to stall his mental decline, and that he’s long decided had no effect anyway. A celebrated novelist now struggling to put pen to paper, Tusker has made quiet, stoic peace with his fate, independently tying up what loose ends of his life he can in the uncertain amount of time he has left. Sam, a classical pianist who has recently put his career aside to care for Tusker, can’t approach things quite so pragmatically, as he clings to fast-fading delusions that their companionship will see them through the worst. Whether he’s unable to accept grimly imminent reality more out of defiant love for his life partner of several decades, or his own cavernous terror of being left alone, is a question that “Supernova” addresses with moving frankness, even when its characters talk gingerly around the issue.
On the face of it, not much happens in “Supernova,” as Sam and Tusker chat, cuddle, argue, say a few goodbyes and take in all the ravishingly autumnal Lake District scenery they can get — though Mike Leigh’s regular cinematographer Dick Pope finds as many planes of beauty in the couple’s duskily lit indoor embraces as in those rolling green-to-ochre landscapes. The drama — and it proves lacerating, in its softly-softly way — comes as the two must gradually drop their tacitly agreed defences of denial and delay, and speak bluntly about what’s best for them individually, landing on quite different answers along the way. This is not a crisis on which any kind of compromise can be reached: Someone has to win, and though “Supernova” doesn’t see the struggle out to its bitterest end, its discreet, elliptical conclusion is sufficiently devastating in what it implies for the couple’s future.
Firth and Tucci are such reliable stalwarts that we tend not to regard their presence too closely in films these days: Almost invariably, they fulfill our expectations of their refined gravitas. But there’s something lovely and surprising in what they bring out of each other here, as they complement and reflect each other’s curtness, evasiveness and occasional spillages of tenderness in the way that long-term couples do. Old jokes and teases are recycled between them with loving half-heartedness, beautifully observed in Macqueen’s writing: “It isn’t even satisfying half the time,” Tusker admits, only to admit with a smirk, when asked why he still bothers, “Because of the other half.”
Playing the partner left behind by dementia can be a thankless task in this subgenre. Witness the comparative lack of awards recognition for the co-stars of Julie Christie in “Away From Her,” Emmanuelle Riva in “Amour” or Julianne Moore in “Still Alice” — though perhaps we’re also looking at a relative scarcity of male protagonists put in the more vulnerable position, a prevailing dynamic that “Supernova” challenges with its thoughtful, unassuming depiction of an everyday gay relationship.
But it’s Firth’s Sam who finally carries the film’s heart, and exquisitely so, as his fear, anger and mounting insecurity lash out the more he tries to remain undemonstrative. (He also pulls off some able, plaintive piano-playing by his own hand.) Eleven years on from his Oscar-nominated turn in “A Single Man,” which called for similarly grieving notes in more embellished, less plainspoken surroundings, the actor may have turned in the performance of his career here — all the more affecting for being in the kind of film that doesn’t put it up in lights. “Supernova” enriches our love for its stars, and announces Macqueen as a talent to invest in, but it’s no preening showcase piece. Whatever warmth it leaves you with is rightly undercut with a plunging, unshakeable streak of sorrow.