Anne Hathaway is blonde and badass in the first trailer for Serenity, her upcoming thriller with Matthew McConaughey, Jason Clarke, Diane Lane and Djimon Hounsou.

She plays a battered wife who turns up on the fishing boat of her ex-husband (McConaughey), asking him to help her kill her violent, slick-haired husband (Clarke). 

Her plea: for McConaughey to dump her man in shark-infested waters so that no man will ever find him.

There are clearly a few wrenches thrown into the storyline. After all, McConaughey cautions they live on an island where "everybody knows everything."

The movie looks stylish, seductive and brutal. It's from writer/director Steven Knight, who wrote the script for Eastern Promises and wrote/directed Locke starring Tom Hardy.

Will he craft the perfect murder... or will Anne and McConaughey blow it? Find out when Serenity hits theaters on October 19.