Who else looked fantastic last night. Uh-oh. Robin. It began with that spectacular entrance, a little dance before a full night behind the table with Len, Bruno and Carrie Ann. Let's get started with... See More
Who else looked fantastic last night. Uh-oh. Robin. It began with that spectacular entrance, a little dance before a full night behind the table with Len, Bruno and Carrie Ann. Let's get started with a look at how she did it. Robin Roberts. Reporter: It was robin's big night in the ballroom and she brought all the right moves. ? I have to tell you all this is a surreal moment to experience this electric atmosphere firsthand is remarkable. Reporter: After hours of prep -- Spin me. Reporter: And a special tour of the ballroom from Tom Bergeron. Wow. You pack a lot in here. Reporter: She was all set for her seat. Venture outside of here. You know, it's safe to stay in your lane but not nearly as much fun. ? Reporter: And, boy, did robin have some tough choices. So many standout moments as the stars delivered emotional performances inspired by the most memorable years of their lives. ? 'Cause all of me loves -- Olympian Meryl Davis owned it with this sentimental approximate trot taking home the first 10s of the season. 10. ? Reporter: And paralympian Amy Purdy brought the crowd to tears with her contemporary dance dedicated to her father who gave her a life-saving kidney. There are not enough superlatives. I hope you know what you are doing for people when they see you dance every week. Reporter: The family ties didn't end there. Danica Mckellar and drew Carey dedicated their performances to their sons. I need her to teach me some of those moves. Reporter: While big time rush star revealed a touching secret. He was bullied as a kid. So many people get picked on. For them to see you, everything is going to be all right. ? Reporter: Another yief for olympian Charlie white but "Real housewife" took a more sultry route turning the ballroom into her bedroom with a rumba dedicated to her husband. Honey, you are the life of the party. ? Reporter: And pop star Cody Simpson brought a modern twist to this jazz routine. Now, Billy Dee, this is something that your doctor said you got to do, right? Reporter: In the end it was Billy Dee Williams' last night in the competition deciding to hang up his dance shoes due to a chronic back condition. You know, I've had a wonderful, brilliant, fantastic blast of a time. And working with this wonderful, beautiful young woman. And here they are right now, Billy Dee Williams, Emma slater. Thanks for coming here and flying through the night to be here. Thank you for having us. Billy Dee, this back problem is serious. You're in some kind of pain. Uh-huh. You can smile about it a little bit. There's just no way to go on. It's -- no, not at this point. This is a whole different -- you know, it's one thing to sit and watch that show, but to participate is -- I mean, it's -- it's a whole different world. Yeah, you can see. It's like four hours a day, six days a week. Four, five hours. Yeah, quite long. Pretty strength ow use. And Emma, congratulations, great job. Talk to us about Billy and the travening and I know you guys worked so hard. Yeah. It was. It was really tough decision but it's kind of an easy decision when you know it's the right thing to do. Bittersweet but we had a really good time and our rehearsals have been just great fun. You know who else looked like she was having a good time. Who's that? Robin Roberts and she set the bar high for any other judge that's coming on. Talk about her performance last night. I mean she was spot-on. She was in there with all of her comments, she was great. She said she was going to bring the viewers, you know,' response to the dancers and did give it that special touch. The speech she made, wow, she's going to be good and she was great. What she was saying was -- she thanked the broadcast and the dancers for the joy that the show brings which it really does and I want to share with you our viewers have been weighing in. Big time. We have a question from Facebook for Billy Dee. And for both of you. What are you planning on doing after leaving "Dancing with the stars"? This comes from Matthew Tatro. Thank you from Facebook. Rest. He's a man of few word, Billy Dee. Tired man. Yes. It's tough to fly through the night and tough to do that show and you did it beautifully. It was so fun last night. Your performances. Your grandkids were there. Were they excited to see grandpa dancing. Oh, yeah, they had a lot of fun. Especially Finnegan, he -- he gave he a great compliment. He never really commits, but he decided to give me a big okay. We're just about out of time. Who do you think is going all the way? This is a tough one? I do like the ice skaters. Lovely people and amazing to watch but candy, she's great too. So is Danica. Amy Purdy. And Amy. Thank you guys for coming in. "Dancing with the stars" Monday night. New dance partners 8:00, 7:00 central right here on ABC.
This transcript has been automatically generated and may not be 100% accurate.