They go to Karl Lagerfeld's luxury Chanel supermarket, of course.
Tuesday saw the fashion showman put on a "Chanel Shopping Center" fall-winter show that featured an audacious Walmart-sized reconstruction and saw the celebrity pair applaud vigorously from the front row. They clearly didn't seem to mind sitting near the canned goods food section.
However, events took a nose dive after the show when the rowdy fashion crowd looted the set.
Here are the highlights of this and Tuesday's other incredible ready-to-wear shows in Paris.
CHANEL'S SUPERMARKET IS SO LUXURY IT GETS LOOTED
The attention to detail was astounding.
An entire supermarket had been reconstructed across several hundred square meters of Paris' Grand Palais.
Guests stared in disbelief at shelves bursting with consumable products especially made for this show: bottles of "Tweed cola," wine branded "Maison Gabrielle," and even grilled bread stamped "CC."
This was clearly a fall-winter show like no other.
Chanel trolleys at the side led on to a tall pile of coconuts next to writing "1 for the price of 2," a fresh fruits and veg section, and large signs advertising Chanel's latest special offers. Instead of discounts they read "50 per cent markup."
"Luxury should be worn like you're going to the supermarket. It's the pop art of the 21st century," said the couturier in high spirits.
At the very least, it's proof that Lagerfeld is fashion's greatest showman.
Though the set was a universal hit, perhaps Monsieur Lagerfeld later had one regret: telling revelers they could help themselves to the produce.
It triggered a stealing-frenzy, with security guards having to swoop in as revelers stripped the shelves. At the exit, fashionistas' bags were actually searched to remove stolen goods. One fashion editor succeeded in making off with a Chanel doormat.
KEIRA KNIGHTLEY, RIHANNA AND CHANEL COOKING OIL
"Pirates of the Caribbean" star Keira Knightley — in a monochrome Chanel dress with tiny waist — rocked the front row alongside her husband, Klaxons singer James Righton whom she married last year.
They entered a cordoned-off area after the show alongside superstar Rihanna near some Chanel cooking oil.
It triggered a media frenzy with a worried Knightley saying, "I think there's a fight breaking out."
Her husband, who watched from the sidelines, seemed puzzled by the luxury supermarket concept. "It's my first Chanel show. It was fairly mad. Is this normal?"
Yes, at least in Lagerfeld's world it is.
THE CHANEL CLOTHES CHANNEL YOUTH AND Colour
Just like a supermarket, Lagerfeld produced a collection that was so varied there was choice for everyone.
With attention given to large rounded shoulders, exaggerated upper torsos, cinched or exposed midriffs and lashings of tweed, Lagerfeld mixed and matched.
Stylish brown tweed was turned into a jumpsuit — with voluminous pockets on the bust and great 80s turn ups.
A section that seemed to channel the designs of artist Vassily Kandinsky provided bursts of colour on driving coats and a pair of bold blue and green leggings. It looked very young, but Lagerfeld quipped after the show: "Never young enough for today's standard. The older the (women) are, the younger they want to look!"
For the fun factor, models carried large leather and silver-bound Chanel shopping baskets as they theatrically browsed the catwalk shelving.
If the show seemed to lack the focus of Lagerfeld's best shows, some fantastic single garments made up for it. One black three-quarter length coat had a lovely fluidity with delicate diagonal ribs.
IRIS VAN HERPEN'S SHOCK TACTICS
The human body was in focus at Dutch designer Iris Van Herpen's sublime debut catwalk show on the ready-to-wear calendar.
Van Herpen likes to shock.
In this show the shock-factor saw three models writhing in suspended square plastic bags that had the oxygen sucked out.
It disturbed several guests as it looked as if the models were in discomfort or couldn't breathe.
In the clothes, embroidered beads on mini sheaths resembled shining human cells on models in jutting boots without heels. While some beautifully executed techno-fabric, silver, cocktail dresses glistened like organic fluid.
Several looks also seemed to turn the body inside out: black and white chubby fur tops had the top slashed off to reveal flaps of fabric like exposed flesh.
The collection perfectly towed the line between surreal artistry and wearability, but next time Van Herpen shouldn't try to frighten guests.
ALEXANDER MCQUEEN'S LITTLE BO PEEP HAS LOST HER WEREWOLF
Sarah Burton produced a cryptic but accomplished show for Alexander McQueen set on an emotive green heath.
A-line skirts in broderie anglaise, large white rounded collars, thigh-high lace up boots and tulle embellishments pointed to an 18th century vibe.
Then, the patches of long black and white fur and animal eyebrows at times looked like Burton was going for a werewolf vibe.
Was she chanelling the beginnings of British gothic horror writing that started in the late 18th century?
VALENTINO'S ANSWER TO THE SWINGING SIXTIES
Valentino 's Maria Grazia Chiuri and Pierpaolo Piccioli gave their diaphanous, and slightly puritanical designs, an injection of 1960s and Pop Art.
Though the design duo they didn't pay attention to the menswear vibe sweeping fall-winter shows so far — and people don't expect uber-feminine Valentino to, either — this show definitely felt more "trendy" than in previous seasons.
The best look was a shimmering silk purple, silver and pewter baby-doll dress with black colour. And some of the harlequin looks were eye-catching, though sometimes a little busy.
It was the couture-infused gowns they did best — after all, couture is almost synonymous with the house.
Fastidiously embroidered butterflies gave a beautiful lift to a sexy sheer tulle cocktail gown and continued with a bird motif on another in deep blue.
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