How is it that Kristen Stewart keeps landing these fantastically millennial jobs, jobs which allow her to mingle with the European celebrity demi-monde while remaining disdainfully apart?

While most of her contemporaries struggle to make ends meet at low-paying jobs in the less-fashionable cities of middle America, Ms Stewart somehow stumbles into gigs such as: personal assistant to Maria Enders, an aging actress based in Switzerland, a job that requires her (Ms Stewart) to help Enders rehearse lines while the two of them hike through the scenic Swiss hills (The Clouds of Sils Maria; 2014); and here, in Personal Shopper, an equally aspirational gig as Maureen, personal assistant to a pouty, high-maintenance, high-fashion model based in Paris, whose sole obligation seems to be to be photographed at high-profile social events while wearing the latest haute-couture fashions, garments selected personally for her by Maureen/Ms Stewart, who, after skimming the cream from the showroom racks at Lagerfeld, Cartier and Dior, slings the logoed shopping bags on her shoulder, straddles her motor scooter and wearily weaves through Paris traffic back to her employer's fabulous apartment. And oh: did I mention Maureen's absent but still devoted boyfriend, who occasionally Skypes from the Sultanate of Oman, where he toils away "configuring the security protocols" of some important internet router or other? Yes: evidently these kinds of jobs exist, so for those of you still in the hunt: don't settle for Walmart; keep sending out those resumés to Paris and Oman.

Assayas is an accomplished and confident director, who, in Personal Shopper, offers up an odd mélange of the thriller and horror genres. The weak point, unfortunately, is the script, which Assayas also wrote, which can't quite withstand the strain of holding this mashup together. The result is a kind of Frankenstein's monster of a movie, where the seams between the parts have begun to fray.

The film's opening is promising, with a suitably disaffected Maureen/Ms Stewart being dropped off at the front door of an isolated and rather ominous-looking house, a house that you just know is beyond the reach of 911. She intends (of course) to spend the night there. Alone.

She's hoping to be contacted by the spirit of her dead twin brother, who had been born with (and died from) a malformation of the heart. Why does she want to be contacted by him, you ask? Well, first off: she wants to know if there is an afterlife—and who better to answer this essential question than one's dead twin? But more pressingly: the house has potential buyers waiting in the wings, who won't commit to the purchase until they are confident the house isn't haunted. From this we can conclude that French realtors keep psychics on retainer.

Interwoven with this narrative thread of "millennial twin dabbling with the occult" we have another: "millennial living in Paris wrestles with the temptation to wear her employer's fancy duds, while trying to decide whether to chuck it all and fly to the Sultanate of Oman to hang out with her boyfriend." What can one do but sympathize?

The film begins to hit its stride (and I suppose at this point I should insert a "spoiler alert") when Maureen receives a series of mysterious text messages on her iPhone: could this be her brother reaching out from the spirit world via iMessage? The tension ratchets up considerably when Maureen/Ms Stewart discovers her employer murdered, lying in a smear of blood on the apartment's bathroom floor, and a shopping bag full of borrowed Cartier diamonds missing. In a nicely executed piece of staging a terrified Maureen takes her iPhone out of airplane mode, and we watch as a sequence of delayed text messages appears onscreen, each one more threatening than the one before. In the final message the sender claims that he/she/it is waiting on the landing just outside the apartment's door.

To find out how this all ends for our millennial you'll have to see Personal Shopper when it returns in general release. There's a teaser trailer for the film here.