"Things We Lost in the Fire" director Susanne Bier is helming the feature film, which is to start shooting in September, Variety.com said.
The movie is being executive produced by Richard Curtis, with whom Grant previously collaborated on "Four Weddings and a Funeral" and "Love Actually."
Curtis' brother Jamie co-wrote "Words" with "Borat" scribe Dan Mazer.
The movie is about an actor who falls in love with his Chinese director, but is forced to express his affections to her through her translator, who in turn has her own agenda, the entertainment industry trade paper said.
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