BY CHRISTINA PASSARIELLO

Paris

In just two months, Donatella Versace has gone from touting $39 hot pants to five-figure gowns.

On the heels of a sold-out collection for retail chain H&M last November, the designer returned to the Paris haute couture catwalk this week after an eight-year absence. "After the success with the mass market, I wanted to say, 'Don't forget who we are!' " said Ms. Versace.

More than ever, high-end fashion houses are selling to the full spectrum of prices and customers. And, surprisingly, cheap-chic brands may be giving couture—astronomically expensive made-to-measure clothing—a new lease on life.

The more a brand ...