Miss Pettigrew lives only for a day, and this film directed by Bharat Nalluri will probably remain for an equally short length in your memory. However, Amy Adams and Frances McDormand deliver deliciously cheeky performances that give weight to a plot line so light it could lift a hot air balloon.

Living in 1939, Guinevere Pettigrew is a middle-aged London governess with a knack for getting fired. She’s the kind of woman who plays by the rules and always ends up with the short end of the stick. Her luck changes, though, when she decides to seize the day and stealthily intercept the address of another governess’ potential job. She soon discovers that the position isn’t quite what the prudish Pettigrew expected.

In waltzes the glitzy, self-obsessed vixen Delysia Lafosse. It’s clear she doesn’t need a governess to do the cooking and cleaning — she needs a “social secretary” willing to sort out her complicated love life. While wide-eyed Miss Lafosse is the type who probably dots her i’s with hearts and always maintains a perfect smile, she is stringing along three guys, two of whom she keeps around solely to further her acting career. She plays the superficial damsel in distress all too well and, luckily, Miss Pettigrew has a talent for getting her out of sticky situations. While Pettigrew attempts to conceal her homeless existence from Delysia’s society friends, she runs into a bump when handsome lingerie designer Joe Blumfield (Ciaran Hinds) shows interest in her non-glitterati attitude. Things get sticky when Joe’s on-again, off-again fiancee Shirley Henderson (Edyth Dubarry) recognizes that Miss Pettigrew is actually a penniless pauper.

Over these very eventful 24 hours, people will fall in and out of love, but the real magic lies in the relationship between Pettigrew and Lafosse. They are a witty duo ­— Miss Pettigrew’s levelheaded but charming attitude is the perfect antidote to the sweet-and-sour Delysia traipsing around like a fairy-tale princess. Their lines may not be laugh-out-loud funny, but their interactions are enough to conjure a smile throughout most of the film.

“Pettigrew” only falters in the moments when it tries to be something more than satisfying fluff. Scenes mentioning World War II feel out of place and do not resonate in the fake reality that these characters inhabit. Delysia’s world is like a fairy tale, and well, World War II isn’t an appropriate replacement for an evil stepmother or wicked witch.

Adams, once again, proves herself as one of the most charismatic actresses of her generation. Granted, this isn’t heavy-handed stuff, but she is able to play the subtly sexual, sweeter-than-apple-pie role without causing nausea. However, be warned: Delysia Lafosse is a touch too reminiscent of Giselle in “Enchanted.” In fact, there were moments when I half expected Adams to break out in song wearing a puffy ball gown.

McDormand also plays Miss Pettigrew perfectly as the good-natured but homely governess who discovers pleasure for the first time. McDormand is innocent and endearing as we witness her rapid transformation. Delysia’s three suitors fill their respective roles with ease and it is impossible to dislike any of them.

“Miss Pettigrew Lives for a Day” may not be the most filling selection on the menu, but does provide 90 minutes of pure escapist fantasy that goes down oh so smoothly. To enjoy it, simply follow Miss Pettigrew’s lead and succumb to the sheer pleasure.