Not quite "The Rachel!" Jennifer Aniston looked nearly unrecognizable while trying to work a shaggy brunette bob on set Wednesday, July 17. See more photos of Jennifer's on set bob at PopSugar.

Aniston hid her long blonde hair under a short brunette wig with side-swept bangs while filming her new movie, Squirrels to the Nuts, in New York City. The 44-year-old adventurous actress got into character by pairing the short 'do with a low-cut blue dress in one scene, and black tank top and dress pants in another.

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Between scenes, Aniston kept cool in the Big Apple heat wave by wearing a navy blue mini dress, fedora and shades. The Friends star also received a special visit from fiance Justin Theroux at her trailer. Her husband-to-be was spotted on set wearing a tank top, jeans, boots, baseball cap and sunglasses.

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On Saturday, Aniston and Theroux, 41, attended pal Jimmy Kimmel's wedding to Molly McNearney in Ojai, Calif. "Jen and Justin seemed very happy and in love," a source told Us Weekly of the couple, who got engaged in August 2012. "She had her hand on Justin's knee for most of the ceremony and was intently listening."

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This article originally appeared on Jennifer Aniston Wears Brunette Bob Wig on Set, Gets Visit From Justin Theroux