In the many beautifully observed working-class dramedies he’s made over the past five decades, the British writer and director Mike Leigh has returned again and again to one simple yet endlessly resonant question: Why are some people happy, while others are not? Why does Nicola, the sullen 20-something in Leigh’s 1990 film, Life Is Sweet, seem incapable of even a moment’s peace or pleasure? By contrast, how does Poppy, the upbeat heroine of Leigh’s 2008 comedy, Happy-Go-Lucky, manage to greet every misfortune with a smile?

Leigh’s new movie, Hard Truths, could have been titled Unhappy-Go-Lucky. It follows a middle-aged North London misanthrope named Pansy, who’s played, in the single greatest performance I saw in 2024, by Marianne Jean-Baptiste.

You might know Jean-Baptiste from Leigh’s wonderful 1996 film, Secrets & Lies, in which she played a shy, unassuming London optometrist seeking out her birth mother. But there’s nothing unassuming about Pansy, who leads a life of seething, unrelenting misery. She spends most of her time indoors, barking orders and insults at her solemn husband, Curtley, and their 22-year-old son, Moses.

Pansy keeps a spotless home, but the blank walls and sparse furnishings are noticeably devoid of warmth, cheer or personality. When she isn’t cleaning, she’s trying to catch up on sleep, complaining about aches, pains and exhaustion. Sometimes she goes out to shop or run errands, only to wind up picking fights with the people she meets: a dentist, a salesperson, a stranger in a parking lot.

Back at home, she unloads on Curtley and Moses about all the indignities she’s been subjected to and the general idiocy of the world around her. Pansy has an insult comedian’s ferocious wit and killer timing. While you wouldn’t necessarily want to bump into her on the street, she makes for mesmerizing, even captivating on-screen company.

Leigh is often described as a Dickensian filmmaker, and for good reason; he’s a committed realist with a gift for comic exaggeration. Like nearly all Leigh’s films, Hard Truths emerged from a rigorous months-long workshop process, in which the director worked closely with his actors to create their characters from scratch. As a result, Jean-Baptiste’s performance, electrifying as it is, is also steeped in emotional complexity; the more time we spend with Pansy, the more we see that her rage against the world arises from deep loneliness and pain.

Leigh has little use for plot; he builds his stories from the details and detritus of everyday life, drifting from one character to the next. Tuwaine Barrett is quietly heartbreaking as Pansy’s son, Moses, who isolates himself and spends his time either playing video games or going on long neighborhood walks. Pansy’s husband, Curtley, is harder to parse; he’s played by the terrific David Webber, with a passivity that’s both sympathetic and infuriating.

The most significant supporting character is Pansy’s younger sister, Chantelle, played by the luminous Michele Austin, another Secrets & Lies alumn. Chantelle could scarcely be more different from her sister: She’s a joyous, contented woman with two adult daughters of her own, and she does everything she can to break through to Pansy. In the movie’s most affecting scene, Chantelle drags her sister to a cemetery to pay their respects to their mother, whose sudden death five years ago, we sense, is at the core of Pansy’s unhappiness.

At the same time, Leigh doesn’t fill in every blank; he’s too honest a filmmaker to offer up easy explanations for why people feel the way they feel. His attitude toward Pansy — and toward all the prickly, outspoken, altogether marvelous characters he’s given us — is best expressed in that graveside scene, when Chantelle wraps her sister in a tight hug and tells her, with equal parts exasperation and affection: “I don’t understand you, but I love you.”