The film is based on real events, and centres on a double honor killing in India. The script has been written by helmer Bill Bennett.
Patel will play a young man trying to escape his vengeful parents along with his girlfriend, while Collette plays a journalist who becomes emotionally involved while covering the lovers' story, Deadline reports.
Patel has been seen most recently in The Best Exotic Marigold Hotel, and will also appear in Aaron Sorkin's upcoming HBO drama The Newsroom.
Collette's Showtime series The United States of Tara, for which she won an Emmy in 2010, ended last summer.
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Watch a trailer for The Best Exotic Marigold Hotel below: