Catherine Deneuve with her sister Françoise, in a still from 1967, The Girls of Rochefort. (Getty Images)

Smell is more than a sense. It is the key that unlocks a lifetime of memories.

I once got into an intense conversation about fragrance with a grocery store cashier because I'd successfully identified her perfume as Charlie, Revlon's '70s scent that my mother wore. (There I was, unloading my cart, head swiveling madly, utterly convinced that my late mother must be somewhere in the store.)

Your mother's perfume can worm its way into your brain and reside there forever. "We have a fully functioning sense of smell by the time we are 12 weeks in the womb," says cognitive neuroscientist Rachel Herz (no relation), adding that one study found that "when crying infants were exposed to a hospital gown their mother had recently worn, they stopped crying."

As teens we rebel against our mothers with weird haircuts and questionable sartorial choices, but our taste in fragrance may be beyond our control. Called "olfactory comfort," we can't help but be reflexively soothed by our mothers' scent – her personal smell fusing in our minds with her chosen perfume.

Beauty mogul Bobbi Brown kept a bottle of a favourite aunt's Je Reviens cologne for when she "needed a hug," eventually using it as the olfactory inspiration for her Bobbi's Party perfume. And after perfumer Annick Goutal's untimely death at age 53 from cancer, her daughter Camille's tribute was the Sac De Ma Mère (my mother's handbag) scented candle, immortalizing the smell of her mother's leather purse with its cigarette, lipstick and face powder contents.

British author Sali Hughes' book, Pretty Iconic, is a compendium of the best beauty products of the last century, but it's also a personal tour through the author's own memories of her mother's and grandmother's scented powders and perfumes.

"The things I remember about my life are my grandmother's Yardley perfume or the lemon-shaped Bronnley soaps," pristine and unused in a dish in the powder room. "You wouldn't wash with them," she adds. "You had to leave them there looking beautiful and charming."

It's not surprising then, the lengths we'll go to hold onto these elusive fragrance trails. Catherine Deneuve enlisted celebrated perfumer Francis Kurkdjian to recreate a perfume belonging to her sister, Françoise Dorléac, who died at age 25 in a car accident, based on the scant two millilitres remaining in an old bottle.

Kurkdjian replicated the scent, (his Maison Francis Kurkdjian Lumière Noire, a heady, rose patchouli perfume, memorializes this project) choosing to age it "in a hot chamber" so it would more closely resemble the degraded sample that Deneuve had been sniffing for years, which her memory now read as her sister. "It's like building a bridge to a past memory," he says.

A version of this article appeared in the May 2017 issue with the headline, "Grace Notes," p. 22.

Copyright 2017 ZoomerMedia Limited