Starring Maggie Smith. Rated PG.

English writer Alan Bennett was already considered a nascent national treasure by 1970, when he bought a small, detached home in North London’s Camden Town. He had no way of knowing that the place would come with its very own built-in terror: a cranky homeless woman with her hideous van parked permanently in his forecourt.

For a long 15 years, she added an odoriferous nightmare to his day job, yielding little to his efforts to, at first, ignore her and, later, comprehend her through his writing. Bennett himself wrote the screenplay for this latest adaptation of what started as a personal memoir—a 13,000-word essay in the London Review of Books. Since then, it has been rewritten and turned into a play, and it now stars Maggie Smith as Mary Shepherd, the former nun, ambulance driver, and concert pianist who complicated Bennett’s already busy life.

Smartly directed by frequent Bennett collaborator Nicholas Hytner (The History Boys, The Madness of King George), The Lady in the Van also stars theatre veteran Alex Jennings as not one but two Bennetts—both the man coping with this slow-motion home invasion and the writer contemplating how to deal with it. That idea looks worse on paper than it turns out to be, although there are a few trailer-aimed moments and flashbacks, plus a blackmailer from the past (played by Jim Broadbent) the movie could have lived without.

More than anything, it’s another great role for the Duchess, and a fascinating study of how we make lemonade with the sour fruit life leaves in our yards.