Lots of strange things make sense once you get schooled in fashion. Case in point: all those outrageous clothes from men's runway shows that you once looked at and thought, "Who the hell is gonna wear that?" Students of style learn that no one is really supposed to wear them. They're runway pieces, fashion's answer to the concept car, made to crank up the wattage of the show. At least, that was how it used to be. Now that the masses are happily adopting slim-cut two-pieces from J. Crew and the like, throwing on a suit has become commonplace. Which only raises the stakes for more aggressive dressers.

No, true-blue runway versions—filled with goose down or tricked out with a built-in parachute—have not been cleared for takeoff. But their cooler, lower-key cousins have. This season, designers for labels like Bottega Veneta, Fendi, Ports 1961, and Valentino flexed their creative and sartorial muscles by giving men wearable suits made not for power lunches but rather for dinner, a bar—a night out. The message? Buy a suit—meant to be worn not at the presentation come 9 A.M. on Monday but for a little fun when Friday night rolls around.

What's refreshing is the spectrum of choices. This isn't just a new silhouette or button stance. You can find sharp touches like contrasting rockabilly collars or more traditional cuts in bolder patterns that nod to Tommy Nutter's heyday. Whatever the flourish, these suits all exude attitude without the gimmicks. For men who are unafraid of fashion and eager to set themselves apart, especially in their downtime, that rhetorical question—"Who the hell is gonna wear that?"—has a different answer: "Me."

Left: Suit ($3,850) by Bottega Veneta, shirt ($295) by Burberry London, tie ($180) by Thom Browne New York, shoes ($1,710) by John Lobb. Runway photos, from left: Valentino, Fendi, Ports 1961.