“I didn’t want to do the 1970s,” said Miuccia Prada backstage at her fashion show in Milan on Sunday night. “But it just came out, naturally. It was an important moment for protest, for humanity. Which is now very necessary.”

As Italian style’s most intellectual designer – a self-proclaimed “leftist feminist” and former Communist party member and mime artist – Prada always has something complex to say about the state of the world through fashion. At her autumn/winter 2017 show her perspective was particularly unsettling.

Prada’s autumn/winter 2017 show put 1970s suits into a concrete art installation. Photograph: Maestri/WWD/REX/Shutterstock

The show was considered thought-provoking before a single model had even stepped on the catwalk. It was staged in a cavernous concrete space-cum-art installation where sharp-cornered beds in creepy motel colours of sludgy green and mustard were spotlit from above, like slabs in a mortuary. If this was some kind of a comment about domesticity, it was not a blissful vision.

The clothes were less chilling and gentler than the setting, however, focusing on tropes of mundane 1970s commuter belt life in strokeable fabrics. Men wore orange corduroy suits and trenchcoats and held brown leather briefcases. Women were dressed in mohair twinsets with socks and sandals.

Their clashing colour combinations and weird patterns – deep teal offset against dappled white and pink floral patterns – transformed a prissy silhouette into something awkward and high fashion. There were also what Prada called “naive gestures” threaded through the collection: shell necklaces on men and jumpers that were decorated with ship paintings, calling to mind the work of the untutored Cornish painter and fisherman, Alfred Wallis.

Prada remains the most influential brand in fashion, from an industry perspective, and backstage journalists and well-wishers hung on to every word and slyly decoded her outfit. Even that was a whirl of contradictions: a sherbet yellow skirt with marabou trim, a grey silk blouse with a mandarin collar, an ornate gold necklace and earrings and a grey V-neck jumper that looked very much like something from Uniqlo.

A model during Prada’s show. Photograph: Maestri/WWD/REX/Shutterstock

“It is impossible to summarise,” she began in typically opaque style. “The main sentiment is to go from bigness to smallness. Of going from something very big to something more human and simple. There is a sense of normality, which is very important. Everybody has too much to do, to follow. Somehow we lose out normal nature.” There was also, she agreed, a sinister air. “A crudeness. It was nasty. With flowers.”

Despite the industry’s continued reverence, Prada has fared less well with customers, posting a slump of nearly a quarter in net income in the first half of 2016. Analysts have laid the blame on over-expansion of stores and on overpriced handbags. Its woes are thrown into sharp relief by the success of fellow Italian megabrand Gucci, whose new creative director, Alessandro Michele, has transformed the brand into something a lot more nuanced and esoteric – something a little more like Prada.

A key part of Prada’s fightback plan is to focus on digital efforts. Before the show the brand posted a series of unsettling videos on Instagram that purported to explain the show’s narrative, featuring smashing crockery and hazy bedroom scenes, with tag lines designed to inspire chin-stroking: ‘Privacy is a luxury’ and ‘The revolution starts at home’. How very enigmatic. How very Prada.