Meryl Streep's greatness—her facility with accents, her plasticity and that uncompromising quality every really lasting actor has to have—has often been used to portray the limits of human suffering. In Julie & Julia, Streep gets to kick up her heels instead. She has such fun with the part of the cookbook writer Julia Child that she's consistently intoxicating to watch.

The gusto of this life is like the little bits of happiness that turn up in other biopics. You keep waiting for the clouds to gather. You know how it is when you're watching a film, and the happiness onscreen is so complete that you know someone's going to have to pay for it. When Child's equally ungainly and boisterous sister Dorothy (Jane Lynch) turns up in Paris, and the ladies chatter like exotic birds, throwing back their red wine by the glass, you think, "Ah, so the sister's going to get cancer." But it doesn't happen.

Streep continues at full sail through the film, elevated a bit on a high heels, and trotting with the happy clunkiness of a Clydesdale. Child's distinctive voice—the whoop of surprise, the trill and warble when she spoke—makes Streep's part of the film enthralling. Cast as her beloved husband (I'll spoil this: nothing fatal befalls him) we have a dapper, droll Stanley Tucci, playing a cultural attaché. Tucci shows the best way to hold your own with a first-rate actor having the time of her life: recede a little and react slyly.

Julia has her crisis—first overcoming a soupçon of prejudice to try to graduate the Cordon Bleu, and then yearning to take the good word of French cooking back to 1950s America. But in this scrumptiously, art-directed version of 1950s Paris, she has a great good time. Watching this woman's oversized delight in food and wine and sex is prime stuff.

But there had to be some way to hold the film together, and sure enough disaster befalls. Half of this film is based on Julie & Julia, the hustled-into-print book version of a blog by Julie Powell. Amy Adams, the most charming young actress alive, plays Julie, and she's still a horror. Powell's schtick was cooking all the recipes in Child's Mastering the Art of French Cooking in one year, a grim marathon conducted in a tiny Queens kitchen. She obsesses over this, while working a day job and browbeating her husband (Chris Messina). Director Nora Ephron tries for frankness in her script by having Julie Powell call herself a bitch. That isn't enough to rehab her.

Ephron may not have the taste or the patience to deal with a girl of our decade, compared to her more idealized notion of life in the 1950s. It's probably inadvertent, but the film has the aspect of a hit job on the blog generation. This is Ephron's best movie by a mile, but the dreary back-and-forth about Julie Powell's problems are hard to bear. It's a study in contrasts, for sure: one person marvels at life, another grinds away at it; one person tries to bring joy to the world, the other tries to figure out the fast track to fame. Give me Julia over Julie any day.

'Julie & Julia' opens in wide distribution on Friday, Aug. 7.

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