It’s always nice to see actresses who are—shall we say—of a certain age get the spotlight in a film worthy of their talent. “Grandma,” for example, was a late-career highlight for Lily Tomlin. It would be nice if “The Last Word” represented a similar triumph for Shirley MacLaine. Unfortunately, it does not. A sappy geriatric comedy that starts amusingly brittle but quickly goes soft, it’s a showcase for MacLaine, but not a happy one.

MacLaine is Harriet Lauler, a hard-as-nails old broad who once ran a successful advertising agency but, through sheer abrasiveness, has alienated everybody in her life—including her ex-husband Edward (Philip Baker Hall) and estranged daughter Elizabeth (Anne Heche). An introductory montage explains how: she’s a control freak who orders everybody around, including her gardener (Gedde Watanabe), her housekeeper (Yvette Freeman) and her hairdresser (Sarah Baker).

That desire to run everything her way comes into play when, after a brush with death (a combination of pills and alcohol that might have been an accident but more likely was not) that ends with snide remarks to an unsympathetic doctor (Todd Louiso), she determines to have her obituary prepared in advance so she can make sure it will be glowing. Why she doesn’t simply write it herself is never considered; instead she barges into the office of the editor of the struggling local paper (Tom Everett Scott) and demands that he turn over his young obit writer Anne (Amanda Seyfried) to research and compose it for her, having noted how the girl had managed to make recently-deceased losers sound like much-loved saints.

So far, so good. Up to this point Harriet isn’t much different from the rich, nasty lady MacLaine played a few years back in a much better film, Richard Linklater’s “Bernie.” But then the plot kicks in, and watching the woman mellow is not a pleasant experience. Seyfried, who for the most part is a rather pallid presence, gets a few laughs out of her frustration at finding Lauler’s acquaintances unwilling to say anything good about her, but Anne is such a drip—a wannabe essayist who occasionally runs home to daddy (Stephen Culp) for support—that she might be blown away by a strong gust of wind.

Not to worry, however: one of Harriet’s accomplishments will be to hook Anne up with Robin (Thomas Sadoski), the manager of an alternative radio station where she uses her collection of old vinyl LPs to get a gig as a morning DJ—a job at which, of course, she excels. In addition to playing matchmaker, she will also determine, in order to spruce up the obit, to “adopt” a disadvantaged kid named Brenda (Ann’Jewel Lee Dixon), a foul-mouthed tyke who becomes her pet, and whom we’re all supposed to find charmingly precocious despite Dixon’s obvious amateurishness on camera. (No chance.) She will also reconnect with Edward, who not too surprisingly retains a reservoir of affection for her, and Elizabeth.

The reunion with her daughter allows MacLaine and Heche to have at it in a scene that, for a moment, brings the picture back to the tone it originally possessed. Unfortunately, it concludes with an extended bout of hysterical laughter that’s meant to provide MacLaine with a show-stopping cadenza that will have viewers rolling in the aisles. Unfortunately, while it does bring things to a halt, it’s probably the audience’s eyes that will be rolling at how embarrassing the exhibition is.

From that point things go downhill quite badly. Harriet, Anne and Brenda have become a little family, and Lauler is ready to live again. An informant from Harriet’s old agency (Joel Murray) arrives to explain how she lost control of the place, which allows her to find closure over her unceremonious departure from the firm she built. But while things seem definitely on the upswing, the results of the tests the doctor ordered after the hospital stay that started the whole obituary thing are still waiting to be heard from. And you know what that means. The ending is schmaltzy in a fashion typical of telefilm fodder.

Still, there is MacLaine, whom director Mark Pellington deferentially gives free rein and who responds with a turn that pushes all the required buttons. She remains a masterful actress, though in this case she employs her considerable skill in a futile effort to give some depth to shallow material. One might have expected Pellington to have taken a firmer hand with the rest of the cast, but his approach remains lackadaisical throughout, and both Seyfried and Dixon suffer from it, though Hall’s avuncular presence makes for some nice moments and Heche adds some welcome edginess. On the technical side the movie is no more than adequate, with the production design by Richard Hoover and Eric Koretz’s cinematography both nondescript. Nathan Matthew David’s score is overbearing, but to compensate there are lots of cuts from pop tunes interrupting it.

One hopes that “The Last Word” won’t be that for MacLaine. She’s far too good an actress for this to be her cinematic swan song.