Since its inception in 2010, the Rockstud stiletto has been responsible for doubling its creator's – luxury Italian fashion house Valentino – revenue. Impressive stuff. The street-style favourites are famous across the world, and have sold out in every which way it has been put on the market over the last five years.

Of course it helps when your two creative directors are veteran accessories designers by trade – and Maria Grazia Chiuri and Pierpaolo Piccioli have shrewdly nutured the growth of the spikey shoe over the last half a decade. And it's worked, last year saw Valentino's revenues up by 36 percent, with half of all sales coming from accessories. 

It seems fellow luxury brands Mulberry and Gucci want a piece of this pie, as the British heritage house recently recruited Céline's accessory designer Johnny Coco as its new creative director, and Gucci announced that its in-house accessories head – Alessandro Michele – would replace Frida Giannini. What the two creatives will bring to the market in a bid to replicate the success of Valentino's It-item mania with the Rockstud, only time will tell...