By Betsy Sherman

The Lady in the Van is quite enjoyable, but has a significant flaw.

The Lady in the Van, directed by Nicholas Hytner. At Kendall Square Cinema and West Newton Cinema.

Maggie Smith in The Lady in the Van.

Alan Bennett was the anomaly in the hip cast of the early ‘60s satirical revue Beyond the Fringe. Best known in that show for his absurdist take on a doddering pastor giving a droning sermon, the pasty, bespectacled Leeds native existed in a lower key than his mercurial cast-mates Peter Cook, Dudley Moore, and Jonathan Miller. He seemed like the spawn of an Alec Guinness character in an Ealing picture.

Continuing on in theater, film, television, and print, Bennett has combined a scalpel-accurate wit with a gentleness of spirit and a resolve to reserve judgment on his characters. What these figures, sympathetic and not-so, share is their ingrained Britishness. The slyly funny new film The Lady in the Van is distilled Bennett. The material came from his real-life experience with the title character, and it has evolved from a memoir to a play and now to a feature. Moreover, the actor who plays Bennett in the film appears on screen simultaneously as both Alan-living-life and Alan the writer.

Prior visits to Bennett’s world are not a pre-requisite. Not when we’ve got the rare chance to see Maggie Smith in a leading lady role, and one that she tackles full-on. The split-personality Alan role is played, with a skill for understatement, by Alex Jennings (Prince Charles in The Queen). At the helm is Nicholas Hytner, who has directed Bennett film adaptations The Madness of King George and The History Boys.

“Whereas my contemporaries movingly chronicle their first tentative investigations of the opposite sex or their adventures in the world of journalism,” bemoans Writer Alan, “I’m stuck with old ladies.” Alan’s life is tangled up with that of his elderly Mam (Gwen Taylor), never mind that she still lives in the north and he’s in London. She has become “raw material” for his art (the film shows a brief bit of Jennings performing Bennett’s great mama’s-boy monologue “A Chip in the Sugar”). Into his life comes Miss Shepherd (Smith), an older woman of sour disposition and no fixed address. When he moves into the picturesque Camden Town section of London in 1970, the van in which she lives is parked down the road. He has encounters with her, and does favors for her, but she’s not really his problem. In 1974, parking restrictions tighten and he lets her live in his driveway. He envisions it will be for a few months; it ends up being 15 years.

Insisting on her self-sufficiency, Miss Shepherd puts up a crusty front and never lets out information about her past. Occasional details, discovered in disparate nuggets, are passed around among Alan and his bemused neighbors (there are nice dry performances by Roger Allam, Deborah Findlay, and Frances de la Tour). She does not, however, hide her devotion to the Catholic faith and its rituals.

Writer Alan, never straying far from his typewriter stationed at the front window, arches an eyebrow in dismay as Life Alan caves in to Miss Shepherd’s demands—especially the one to use his bathroom. His narration lists the mixture of awful smells she brings in and leaves behind, and we see much use of disinfectants. Bodily functions, and the English aversion to them, figures into the story in its sexual sense as well, because Alan is a closeted gay man who, even as the decades go by and taboos recede, can’t assert in public what most people seem to know already (even Miss Shepherd figures out the meaning of the occasional nocturnal visits of unfamiliar men).

Although Alan narrates, the screen adaptation isn’t strictly from his point of view. A prologue enigmatically shows an event from earlier in Miss Shepherd’s life, one that will affect her deeply. Hytner sometimes places the camera in her closely guarded domain, the van. And even though the two protagonists are figuratively tethered, we follow her on excursions and into that most private of places, the confessional. Bennett gives the priest a classic quip after Miss Shepherd asks yet again for forgiveness for one particular act: “Absolution is not like a bus pass. It does not run out.”

The storytelling strategy involves Life Alan chiding Writer Alan because “she didn’t say that” or “it didn’t happen that way.” Hence we make allowances for some passages in which exposition is a bit pat or sentiments improbably flow to the surface. One is a literal “hair down” moment: Smith is always seen wearing a scarf wrapped around her head under a cap, but one night she exposes her greasy-but-lovely gray hair in order to give Alan, and us, some insight into a turning point in her past. It’s a moving passage, but so too is the one in which Smith gets to smile: when Miss Shepherd is completely absorbed in swathing her van with lumpy yellow paint. For Alan’s part, he feels the irony that Miss Shepherd thrives, in her own weird way, while his mother declines into dementia.

The Lady in the Van is quite enjoyable, but has a significant flaw. The subject of music plays a great part in Miss Shepherd’s story; this can be gleaned from what’s depicted in the opening credit sequence. By the end of the movie it’s clear that Bennett believes the greatest tragedy in Miss Shepherd’s life is that she has tried to cut music out of it. But Hytner fails in making us feel that aspect of the story viscerally. Granted, it’s challenging to express an absence. It sure doesn’t help that the director felt obliged to use the same syrupy-jaunty score that blights most British screen comedies. It may be time to step away from the venerated George Fenton and find a composer with a fresh approach that, by the way, supports your thesis statement.

Betsy Sherman has written about movies, old and new, for The Boston Globe, The Boston Phoenix, and The Improper Bostonian, among others. She holds a degree in archives management from Simmons Graduate School of Library and Information Science. When she grows up, she wants to be Barbara Stanwyck.