What's for dinner? Meryl Streep is taking on 'Transformers' and 'Harry Potter' as culinary legend Julia Child in 'Julie & Julia,' in theaters August 7, and we've got an exclusive look at her incredible transformation!

"Julia Child was a larger-than-life character," says Meryl. "She had a passion for living. She had real, true joie de vivre. She loved being alive, and you felt that from her show and the books she has written."

Based on the bestselling memoirs Julie & Julia and My Life in France, the film intertwines the lives of two remarkable women in two different time periods: Julia Child (Streep) and her rise to prominence as the world's first female "do-it-yourself" culinary authority; and Julie Powell (Amy Adams), a lowly cubicle worker who decides to take on a writing assignment: Go through Child's cookbook and create 524 recipes in just 365 days.

"In [the early '60s] television was a fairly formal affair, and people were not used to the real freshness of a personality undiluted, unscripted," says Meryl. "People were responding to the fact that they were really meeting a real person on television."

"It's about diving in and not being intimidated by things that seem overwhelming," explains Amy of the movie. "I hope [audiences] go home, cook a good meal for their friends, pour a glass of wine and sit around and talk about the movie."

Directed by Nora Ephron ('Sleepless in Seattle'), 'Julie & Julia' also stars Meryl's 'The Devil Wears Prada' co-star Stanley Tucci, Chris Messina and Linda Emond. Bon appetite!

Watch ET for more with Meryl and Amy in 'Julie & Julia'!

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