The Multiplex department store hosts fashion, fragrance, technology, furniture, accessories, beauty and food from a collection of more than 30 international brands and designers. Tom Dixon's machine component-shaped Cog lights and reflective Brew coffee sets are also among the collection of products on display.
"It's a parasite on Selfridges," Dixon told Dezeen. "Maybe it's like the navel in a navel orange, or a world within a world. I don't want to be a parasite but there are benign parasites."
The shop inhabits the disused 20,000-square-foot Old Selfridges Hotel space, which is attached to Selfridges' flagship Oxford Street store. HTC previously converted the space into a temporary skatepark.
The concrete interiors have been draped in folded silver foil hangings, which according to Dixon take their reference from the International Space Station and the toilet in artist Andy Warhol's infamous New York studio, known as the Factory.
Dixon explained he'd been "pestering" Selfridges for two years for an opportunity to do something with the space. He described the installation as an attempt to reclaim the world of retail from the ever-growing threat of online stores, and a chance to create a more engaging environment.
"I wanted to see what happens if you take the raw energy that exists in London elsewhere and stick it right bang in the middle of one of the biggest department stores in the world," he said.
"What happens if you stick the people that are normally ghettoised in smaller design shops or less rich environments all together, and give them a platform to speak?"
This attitude towards retail follows on from his ideas for The Cinema exhibition in Milan earlier this year, where the designer's newly unveiled products were sold directly from the space.
The collections on display at Multiplex are eclectic, from Haeckel's all-natural Margate-made fragrances, to British eyewear brand Cubitts, which will be hand-making charcoal and concrete frames in-store for customers.
The mix of products came about through "organic growth" – a mix of bringing together Dixon's network of contacts, and cold-calling promising brands and designers.
"If I'd ended up with a big art department or toy department, I would have been happy, because I wanted to make unexpected connections, so we cast the net wide," he said.
"I don't think people live in departments like you do in proper department stores, where toys are on one level and beauty is on a whole floor right at the bottom," Dixon added. "You do your makeup in the kitchen, or your work on the dining table. People don't live in the way stores separate things."
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It's not the first luxury department store collaboration for Dixon, who partnered with Harrods in 2014 to lend his name to a sandwich cafe.
Multiplex will remain open until 15 October 2015, as part of this year's London Design Festival, which takes place from 19 to 27 September.