Mila Kunis has a less than glamorous day at the office on the set of her new film

Mila Kunis swapped Dior for drab on the set of her new film, The Angriest Man in Brooklyn, as she filmed scenes with co-star Robin Williams in the East River

Mila Kunis swapped Dior for drab on the set of her new film, The Angriest Man in Brooklyn, as she filmed scenes with co-star Robin Williams in the East River.

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The Black Swan actress, who recently began a romance with That 70s Show co-star Ashton Kutcher, was spotted dripping wet in blue hospital scrubs as she dove into the East River to help co-star Robin Williams, who plays a man trying to determine what he will do in the final moments of his life in the comedy-drama, The Angriest Man in Brooklyn.

No stranger to suffering for her art - the actress plummeted down to 95 pounds after losing a stone-and-a-half for her role as a ballerina in Black Swan - Mila soaked up her new role (literally!) as she lent Williams a helping hand out of the river.

Ever the good sport, she even managed to muster a smile... despite coughing up river water from the scene and having to re-immerse her head in a wet bucket of water between takes.

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Mila also showed off her running skills in an earlier scene, where she was filmed dashing through the streets in trainers and a trench coat, with her hair in a swept-back ponytail.

Meanwhile, boyfriend Ashton is having a distinctly less unpleasant time on the set of his TV show, Two and a Half Men - he was last spotted canoodling up to a lingerie-clad Miley Cyrus in bed. MILA KUNIS: STYLE HIGHS & LOWS

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