Miss Pettigrew Lives for a Day 

If there’s one good thing about this frothy period comedy, it’s that it represents the fulfillment of a dream deferred. Seventy years ago, an author of “bodice rippers” named Winifred Watson published Miss Pettigrew Lives for a Day, the tale of a straitlaced middle-aged governess who, thanks to a misunderstanding, spends 24 hours as the “social secretary” of a free-wheeling party girl. Daring by the standards of the time, Miss Pettigrew was an “instant hit,” according to Watson’s 2002 obituary in the U.K. Telegraph. Plans for a film version followed, with Billie Burke (Glinda the Good Witch from The Wizard of Oz) slated to play Guinevere Pettigrew.

Unfortunately, Pearl Harbor intervened. With bombs falling, irreverent comedies were no longer the order of the day. And Watson, a former secretary who scribbled her manuscripts in the office, missed her moment in the Hollywood sun. An interview quotes her as saying she “wish[ed] the Japanese had waited six months.”

Now, six years after its author expired at the age of 95, Miss Pettigrew finally hits the screen. It hasn’t aged well. Though the movie scored two accomplished, amusing actresses in the lead roles, and “Anything Goes” burbles on its soundtrack, it fails to effervesce like a product of the Cole Porter era. Instead, Watson’s story, adapted by David Magee (Finding Neverland) and Simon Beaufoy, comes off like one of those stale old farces that’s considered “safe” for high schoolers to perform.

It didn’t have to be this way. Real 1930s screwball comedies, full of uptight gents and “dizzy dames,” weren’t just risqué entertainments for their era — the best ones are still wickedly funny. Miss Pettigrew features some of the rapid-fire dialogue typical of that era, but weds it to a plot that would have seemed old hat to Katharine Hepburn or Carole Lombard.

Frances McDormand — star of Fargo and spouse of Joel Coen — plays Miss Pettigrew, a vicar’s daughter who, for reasons never adequately explained, keeps getting fired from her jobs tending the offspring of London’s elite. Starving and desperate, she lies her way into the posh apartment of Delysia Lafosse (Amy Adams), an American nightclub singer looking for her big break in the West End. The chirpy redhead — who pretty much defines “dizzy dame” — needs a chaperone of sorts, someone to assist her in the task of juggling three lovers who each want to be her only feller. There’s the sleazy club owner (Mark Strong) who bankrolls Delysia’s swanky, Art Deco home and wardrobe, the callow theater producer (Tom Payne) who could make her a star, and the penniless pianist (Lee Pace) who truly loves her.

Gee, wonder which one she’ll choose? In a classic screwball comedy, the answer wouldn’t be obvious. But Miss Pettigrew quickly turns from farce into familiar romantic fable. Even as the tarty singer helps the governess loosen up and live a little, Miss Pettigrew becomes her employer’s moral lodestar, sternly reminding her that “Love is not a game.” She also gets her own love interest — Ciarán Hinds playing a very straight, very dull designer of frou-frou lingerie.

A cast this good deserves a snappier script. A fine-boned actress who appears to be aging naturally — rare these days in Hollywood — McDormand conveys both the prim and naughty sides of her character, even if the film never seems to figure out how they fit together. Adams is a natural for this über-girly role, and she’s as much fun to watch as you’d expect — until you realize her character is going to stay caricature. Playing a scheming, nasal-voiced fashion designer, Shirley Henderson (Harry Potter’s Moaning Myrtle) manages to give her role a bit more depth.

Director Bharat Nalluri reminds us of the world beyond this silly social scene with scenes in which wailing air raid alarms disrupt the party — just as they disrupted the booming career of Winifred Watson. But a biopic of the forgotten novelist herself would probably pack more surprises than this tired, long-delayed adaptation.