Night after night, the pop superstar wowed in form-fitting frocks, midriff-baring tops, and sexy minidresses that showed off her lean legs. But on the Wednesday, Dec. 19, show -- part one of the competition's two-part season finale -- the 31-year-old mentor kept her look modest and let her star contestant, Carly Rose Sonenclar, have the spotlight instead. Sporting a black Yves Saint Laurent jumpsuit, black-and-white heels, and a long Erickson Beamon beaded necklace, Spears was the picture of understated chic.
Sonenclar, on the other hand, looked -- and sang -- like a true star-in-the-making. Facing off against Fifth Harmony and Tate Stevens for a $5 million recording contract, Spears' 13-year-old protege performed pitch-perfect renditions of Nina Simone's "Feeling Good," Leonard Cohen's "Hallelujah," and LeAnn Rimes' "How Do I Live" -- with Rimes herself!