Exclusive: First look at Christopher Kane and J Brand collaboration

On some level, designers instinctively know that whatever they put on the catwalk, its success depends on how compatible it is with skinny jeans. This is especially true of footwear, 98 per cent of which is now designed to work with a drainpipe leg, hence the enduring popularity of the high-heeled ankle boot and shoe-boot.

Yet viewed objectively – i.e. not through the prism of habit – the skinny is a highly suggestive, unforgiving item of clothing. In extreme cases, a tight jean gets gynaecologically explicit.

It was Alexander McQueen, in the early Nineties, who reshaped trousers, elevating them from a safe also-ran fashion garment to something much more provocative and subversive. The late Eighties had been all about the sexy power suit, the star of which was a mini-skirt; not a trouser to be seen. The McQueen bumster was masculine and outrageously low-cut on the hips, hence its soubriquet, and narrow. An ocean of whale tails (the evocative name for the visible G-string that was the inevitable result of wearing such a low waistband) was the result, as scores of “premium” denim brands launched to take advantage of the hipsters revival.

Rudes went one further when he launched J Brand in 2005. Its first design was a skinny leg – in dark denim. “I wanted something completely different from all those other Californian premium denim ranges,” he says. From the start, J Brand was conceived as an aspirational fashion label that would ride out the denim craze.

By increasing the rise on his jeans to nine inches, Rudes created a silhouette that elongated the leg, held in the tummy and, by ending just above the navel, created the illusion of a slimmer waist. Kate Moss gave them her blessing and J Brand became a worldwide phenomenon. Niche companies such as Kova&T, a leggings business part-owned by Russian socialite Dasha Zukhova, began selling leather and sequinned leggings on for £400 – £500, prices that seemed ludicrously high, but sold out.