It???s not often that a ghost story serves as a backdrop for some seriously chic fashion, but Personal Shopper, the new thriller starring Kristen Stewart, has just raised the bar.Stewart plays a personal shopper responsible for organising designer clothes and jewellery for a celebrity client.Though her character, Maureen, lives in jumpers and jeans, her glamorous job involves dealing with treasures from Chanel and Cartier - which, one imagines, is not a huge leap from the actress???s real life.

Costume designer Juergen Doering was responsible for the wardrobe, and worked with director Olivier Assayas and the cast to piece together his own impression of how it should look.???First I read the scriptand I asked Olivier to tell me in three adjectives what he thinks about each character,??? explains Doering.???Then I looked at the cast - so I led with the character first and the person second.Then I went to the actors and, without telling them what the director had said, I asked ???How did you get this part and how do you see it????Because Olivier likes for people to feel the character and feel the clothes.???

There???s a noticeable difference between Maureen???s day-to-day clothing and the more elevated style of her boss.???We were thinking that Maureen???s American, she???s in Paris, she???s wearing jeans, she???s a little bit rugged - sneakers, vintage, sweaters,??? says Doering.???I looked at some vintage Fruit of the Loom sweaters at a shop in Paris, and was looking for things that you could believe a girl like this had picked at the flea market.The flying jacket in brown leather, very manly, for when she???s always on the bike - a young person will try things.???

As the film progresses - spoiler alert - Maureen sneakily borrows and wears some of her client???s designer pieces, including a Vionnet organza gown with a harness, something that was specifically requested by Assayas.???I was looking in all the couture collections for a harness dress,??? says Doering.???The director said ???Maybe it???s a harness over a dress, or maybe it???s part of the dress.???In the end I saw it at Vionnet and Olivier liked it immediately.We chose black because there is something ambiguous about her personality: she says she hates the job she is doing and the girl she is picking the things for, but when she comes to desire men, she wants to be that woman she hates.???

Maureen also borrows a silver sequinned Chanel dress.As Stewart has fronted several Chanel campaigns, it was no surprise to see the fashion house popping up in her movie - though Doering says there was no contractual obligation involved.???We know the team at Chanel well, but if we didn???t find what we wanted, we had no pressure,??? he says.???I asked the girls there, ???Do you have something with sequins???? and they said ???Oh we have this old dress that no one has worn before.???And I saw it and I thought ???Oh, this is it.??????It may be the only time you???ll see Stewart in a Chanel dress that doesn???t fit like a glove:???Of course we didn???t fit it onto Kristen, because it is not supposed to be her own dress.She feels uncomfortable in the dress, it???s not hers - but she likes it because it???s not correct for her to wear it.???

Though the contrast between Maureen???s casual wardrobe and this highly polished eveningwear is visually dramatic, it somehow feels like a natural fit for Stewart.The actress is known for her grungy personal style of T-shirts and Converse, but she???s also a muse for Karl Lagerfeld and a fixture on the front row.Working with her was easy, explains Doering:???Kristen knows her stuff.She loved Chanel before she was famous.For her it was easy to jump from the jeans to the dress, no trouble.???

He clearly felt that they had a meeting of minds.???Often actresses they have no taste!??? he laughs.???So it???s good to actually have a conversation with someone who knows.???

Personal Shopper is in cinemas now

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