Palme d’Or-winning British filmmaker Mike Leigh, known for his embracing of kitchen-sink realism, and commitment to extensive rehearsals and improvisation with his actors, needs no further introduction. For his 16th feature, Tender Loving Care, which the director has previously said is potentially his final film, he remains immensely hopeful, despite interjections of pain and the realities of life. In committing a wholesome take on the “secret lives of social workers” premise to the screen, he reveals a genuine earnestness to stay optimistic – but never superficially so. The film premiered at Toronto as a Special Presentation and is now vying for the Golden Shell in San Sebastián’s main competition.

Amy (Kate O’Flynn) and Rosie (Alice Bailey Johnson) are committed social workers in their late thirties, the former having moved back into the latter’s flat after a harrowing breakup. Yet, both remain on the up and up, spending their nights commiserating about work and disappointing suitors over copious amounts of white wine, all after long days seeking to be present for fostered teens and ageing loners alike. Visits to Amy’s parents lead to conversations regarding systemic issues within their social environment. The dynamics change when her father, Geoff, starts to behave strangely in his old age, forcing Amy to turn inwards and reflect on the unknown as it applies to herself now, rather than others.

Leigh casts his partner and frequent collaborator Marion Bailey (also the mother of Bailey Johnson) as Amy’s mother, Birdie, while Paul Jesson, best known for his stage roles, plays Geoff. The two together cultivate the film’s most memorable scenes, earning real laughs from the audience as they bicker, good-naturedly. This is also a perfectly timed role for leading lady O'Flynn, who made waves with her Emmy Award win just days ago, which she earned for her supporting role as the oddball mayor’s assistant in the Apple TV comedy-horror series Widow's Bay.

The filmmaker begins simply with a sound over the opening credits: the quiet marimba-forward score by Gary Yershon, which twinkles its way through the story. The music sets a light, naturalistic tone for the movie, which is inverted by an over-exaggerated, theatrical acting style – even more so than in his other, more recent films. The two consume white wine like it’s water, and their echo chamber-like reflections on the state of the British welfare system occasionally seem like over-enthusiastic preaching to the converted. Audiences will have to decide for themselves to what extent they can embrace these choices, which start to tip the characters into an abstraction of stereotypical thirtysomething-year-old white British women when the camera gets too close, the laughter becomes a strained guffaw or a quip becomes too hammy.

Featuring a delightful amount of knitwear, Tender Loving Care doesn’t grip as much as Leigh’s other works, despite its honest core. Regardless, the 83-year-old filmmaker gets at life’s universal, bittersweet realities – of love, ageing, regret, friendship and more – without the need for melodrama, which is something we can all appreciate.

Tender Loving Care is a UK production by Thin Man Films. Cornerstone Films Limited holds the rights to its world sales.