If you can imagine one of Tennessee Williams’ family plays scrubbed up, made nice, and turned into a period road movie, you’ll have some idea of what “My One and Only” is like. Based on the autobiographical memories of actor George Hamilton, it’s an affectionate portrait of his mother Ann Devereaux (Renee Zellweger), a Southern belle who leaves her band-leader husband Dan (Kevin Bacon) when she discovers him—again—with another woman and abruptly takes her teen sons Robbie (Mark Rendall) and George (Logan Lerman) on an impromptu car trip to find a new husband—and them a new stepfather—from among her past beaus. It’s a sweet, sentimental, occasionally slightly naughty, attractively mounted piece of old-fashioned hokum that will appeal to audiences, mostly female, of a certain age while it will leave most others wondering whether it wasn’t actually made in the fifties as well as being set in that decade.

Certainly Zellweger seems to be having fun as the always well-made up but aging beauty who can’t be deterred by anything from the belief that things will turn out fine, however many minor calamities the trio face on their journey. Beautifully coifed and costumed and shot in what seems a perpetually glowing aura by cinematographer Marco Pontecorvo, she’s looks as though she stepped out of an upper-scale glossy advertisement of the time, and there are plenty of flattering close-ups of her smiling radiantly or pursing her lips in sadness to satisfy the most rabid connoisseur of such elegant, if slightly dotty, heroines of the past.

Under Richard Loncraine’s undemonstrative direction, the youngsters playing Ann’s very different sons come off well, too. Rendall is exuberant as the swishy, eternally supportive Robbie, who wants desperately to be an actor and consistently wins the lead in the school play, though he’s always yanked from the stage before the first performance for one reason or another. But it’s Lerman (recently seen to much less advantage in the title role of the atrocious “Gamer”) who really excels in a role that’s less showy but far more important—that of the dour, serious son with a literary bent (his favorite character, of course, is Holden Caulfield) who’s torn between love for his mother and a desire for stability and ordinariness she can’t provide. And his residual love for his father, accompanied by the belief (erroneous, of course) that the philanderer wants him back, makes things all the more difficult. It’s not an easy part to play, and Lerman does so with a degree of restraint that’s actually quite touching. (The script, however, doesn’t help him with the occasional joke about George’s dislike of sunshine, which—heh, heh—clashes with our knowledge of the older Hamilton as perpetually tanned.)

The men in Ann’s life are a more variable group. Bacon is, as usual, excellent, though he looks so emaciated one may honestly be concerned about his health. Among the prospective husbands-to-be, Steven Weber is overly broad as an unsavory guy with a need for cash, Chris Noth stolid as an ex-military man with a bad temper, and Eric McCormack all toothy smile as a caddish young grandee. But the frequently annoying David Koechner underplays nicely as a Missouri paint salesman who actually proposes—though something untoward intervenes—and Nick Stahl is excellent as Bud, a lower-class young man who’s hardly a marital prospect but treats Ann kindly at an especially difficult time (a sequence that as a whole comes across as contrived).

The rest of the cast is equally hit-and-miss. Robin Weigert and J.C. MacKenzie are quite good as Ann’s sister and brother-in-law, with whom the family spend some time in St. Louis at a low ebb in their fortunes; she’s a bit too strong at some points, but his calmness is a fine balance to her. And Molly Quinn is engaging as Bud’s sister, who’s obviously sweet on George. But Troy Garity and Phoebe Strole come on awfully strong as an ex-soldier and his girlfriend whom Ann and Robbie make the mistake of giving a ride to at one point in their travels.

Visually the picture looks gorgeous, the sumptuous period production design (Brian Morris), art direction (Guy Barnes, Halina Gebarowicz), sets (Bryony Foster, Wendy Ozols-Barnes) and costumes (Doug Hall) adding to the lush appearance along with Pontecorvo’s rich widescreen cinematography. The score, with original music by Mark Isham complemented by a selection of period songs chosen by Steve Lindsey, adds to the atmosphere as well. And the sky-blue Cadillac Eldorado the trio travel around in deserves mention, too, as a silent supporting character.

“My One and Only” closes with an overly cute twist that explains how George becomes a film actor, or at least a movie personality. That ending isn’t remotely plausible, but then the entire picture has the ring of a fairy-tale rather than a memoir. But it’s a fairy-tale older viewers in particular should find a pleasant picaresque.