Sunglass styles are usually cyclical. The aviators, club-masters flat tops and cat eyes all return to the fore periodically, with each year having its own signature novelty shape to slot in between the regulars.
The mirrored lens had its moment last year, as did the OTT embellished styles à la Dolce & Gabbana.
But for those wanting the 4-1-1 on this season's emerging shade, look no further than Balenciaga (obvs) for inspiration.
Somewhere in between a cat eye lens and a flat top, this narrow rectangular style is the one to emulate this season.
The turned up eyewear has been all over the faces of fashions favourite darlings, with Kendall Jenner, Gigi Hadid, Katy Perry and Rihanna leading the way as per usual.
The Balenciaga options aren't available yet to buy - though obvs Kendall already has her hands on a pair, because of course she does. But there are other options for those thinking of taking the half-cat plunge.
Andy Wolf has some half frame options, Le Specs 'The Last Lolita' glasses are a narrow take on the cat eye, Rihanna's Dior collection has to be considered, Elizabeth and James have some vintage inspired cat-eyes which are on the narrow side.
Right, we're off to get ourselves a pair (or five).