PHOTO: Katie Holmes Films New Movie in Dowdy Bridesmaid Dress!

Credit: Bobby Bank/

She once made the boyfriend jeans famous, but Katie Holmes may not be able to do much with a bridesmaid dress!

The 30-year-old actress -- who shot scenes for her new film, The Romantics, in Long Island, New York -- donned a matronly silver-blue satin knee-length gown with beaded embellishment on Tuesday.

Holmes -- who debuted her clothing line with stylist Jeannie Yang, Holmes & Yang in September -- topped off the look with braided hair and gray heels.

In the wedding scene, her character, Laura, serves as a bridesmaid at the wedding of her friends, played by Anna Paquin and Josh Duhamel. (The film also stars Elijah Wood.)

"You'd think she was 35 based on how she carries herself," a source tells the new issue of Us Weekly (on newsstands now).

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