♪ ♪ ♪ ♪ ♪ skinny so skinny ♪ shout out to the "the skinny" and the latest couple to step off the stage of "dancing with the stars." >> that's right, week three of season 18 saw billy dee williams and emma slater bowing out. but they weren't voted off. williams is retiring from the competition under the guidance of his doctor. the 77-year-old says he has a chronic back problem and it kept him from continuing to compete alongside his pro partner, emma slater. >> you know, i've had a wonderful, brilliant, fantastic blast of a time. >> he's been sensational. honestly, i love you so much. i'll never forget it. >> last night also saw its first guest judge of the season. check her out.