Coutesy of Versace

January Jones' latest look features neither pastels nor Jackie O. silhouettes, and would certainly make the prim and proper Betty Draper redden with embarrassment. But we're positive ex-hubby Don would approve.

Courtesy of Versace

The "Mad Men" star and newest Versace model's Spring-Summer 2011 campaign for the brand has been unveiled. In the sexy ads, shot by Mario Testino in London, Jones poses in the buff, clad only in Versace accessories, including bags, shoes, sunglasses and optical frames, according to WWD.

"I am always on the lookout for the next Versace blonde... and in January I feel I have found a perfect Versace woman for the 21st century," Donatella Versace told WWD. "She is chic and elegant but deeply sensual too."

Not all of Jones' TV alter ego has been lost in the transition to Versace vixen: The '60s-inspired bouffant hair and makeup come courtesy of Betty.

Meanwhile, click here for January's style evolution.

And check out Kate and Will's engagement pics, also snapped by Testino.