Patricia Clarkson brings her usual delicacy and class to a toothsome starring role in “Learning to Drive,” a gentle-natured if unimaginative allegory about trust, communication and intercultural understanding.

As the film opens, Clarkson’s character, a New York book reviewer named Wendy, is being dumped by her husband of 21 years. The morning after a tearful ride home in a yellow cab, the driver, Darwan (Ben Kingsley), comes back to her Upper West Side townhouse to return a manuscript she left behind.

It turns out that Darwan – a prim, ramrod-postured Sikh who lives in Queens – provides driving lessons on the side. Wendy, who doesn’t drive, signs up, putatively to be able to visit her daughter (Grace Gummer) in Vermont, but in reality to open the passenger door for a raft of convenient metaphors.

In the not-so-subtle hands of screenwriter Sarah Kernochen and director Isabel Coixet, the symbolism in “Learning to Drive” is about as obvious as a flashing “Construction Ahead” sign. Not only does Wendy confront her fears, but under Darwan’s gentle tutelage, she’s reminded that it’s important to keep moving forward, to learn how to pick up signals and, of course, to keep venturing out of her comfort – er, parking – zone, however gingerly.

Although Wendy’s marriage is falling apart, Darwan is entering into a union arranged by his relations back in Punjab. His wife-to-be is portrayed by the wonderful Sarita Choudhury (“Homeland”), but she’s sadly underused in a film that presents Sikh rites and rituals with little more than touristy curiosity.

Similarly, Kingsley’s performance, while suffused with deadpan humor, never clicks sufficiently with Clarkson’s to create the chemistry we’re supposed to buy into by the film’s end. Coixet tries to liven things up with jolts of hallucinatory magic realism, when Wendy spots her ex-husband and estranged father during her tentative travels.

“Learning to Drive” would be an entirely inert expedition were it not for Clarkson, who plays against Kingsley’s sentinel of propriety with her signature radiance and birdlike gracefulness. Their styles fuse nicely with the unassuming tone of a film that’s content to hum along pleasantly, never hurtling into a higher gear but never stalling out completely, either. Rated R.