There could almost have been a Celine convention going on in the tennis club where Phoebe Philo showed her second collection for the label. Up and down the ranks, dozens of women were proudly displaying their Celine allegiance in camel coats, tux jackets, wide-legged high-waist pants, silk blouses, leather T-shirts, silver-heeled boots, and sandals. Almost the entire Spring collection was there somewhere, save for the sheer trousers (and it's a fair bet someone has those at home).

That the above bears noting is a gauge of the huge significance of Philo's comeback. What she accomplished in restoring the status of rational, classy daywear last season has finally shattered the personal-purchasing moratorium that set in with the recession. Now women have seen what they want, impulse buying is back, and the atmosphere in the house was strumming with the collective will that Philo would follow up with more to keep the spending valves open.

She did so in wave after wave of clothes that fed the pent-up desire for grown-up, flattering, simple but sexy dressing. In her own words: "Strong. Powerful. Reduced." Narrow navy funnel-necked coats and dresses, slim cropped-at-the-ankle kick flares, A-line skirts, and cream silk blouses started it off—all styled in a no-fuss manner with sheer black tights, riding boots, or high-heeled loafers. At a stroke, it carried the wholeness, simplicity, and confidence of a definitive look, perfectly judged and attainable.

Part of the genius is the way Philo has reframed the sullied term "luxury" by harnessing the DNA of Celine—a Parisian bourgeois sportswear label that was at peak fashionability in the seventies. Her skillful deployment of leather is part of that. She did it with her placement of deep, smooth patch pockets on the sides of shifts and peacoats, as well as in her Helmut Newton-esque black patent wrap skirts and a black double-breasted military trench, belted with a domed brass buckle.

The variety of Philo's outerwear was amazing—spanning a chic-casual navy hooded parka-coat hybrid, slim three-quarter jacket-coats, and a stunning cream teddy-bear shearling cape. Alongside that, a plethora of daywear options focused on separates—a refreshing breakaway from the dress obsession that has stuck fashion in a rut for too long. For evening, she sustained that sense of practical reserve in a cutaway pantsuit with a tunic fluttering beneath it, and two outfits with sculpted black paillettes. None of it was body-baring, none of it showy. Yet it still exuded the calm sense of assured sexuality that adult women have been waiting for since Helmut Lang left the runway. The fact that Philo chose to stage this show in the very venue in which he presented his final collection can't have been a coincidence. In her own feminine way, she is picking up the cause for women exactly where he left off.