The judges on "Dancing with the stars" called Amy Purdy a wonderwoman. She is. The first dance with Derek hough put them in a tie for third place and brought the audience to its feet. Giving us chills... See More
The judges on "Dancing with the stars" called Amy Purdy a wonderwoman. She is. The first dance with Derek hough put them in a tie for third place and brought the audience to its feet. Giving us chills at home. Cameron Mathison went behind the scenes. Reporter: While Amy Purdy was shake her moneymaker, all of America was shaking their heads. She is able to move on not one but two prosthetic legs. You got a bloronze medal in the olympics and a gold here. I have legs for competing. And I have dancing legs. Reporter: She makes it look effort less. Her limbs do come with limitations. The thing with prosthetic feet, you can't have all this crazy motion or you would be all over the place. It's mechanical and outside of your body. Reporter: After earning an impressive 24 last week, she may have been an underdog coming in. But no one considers her an underdog now. Is there anything you're choreographing that is not possible because of the limitations of the prosthetics. Thinking ahead, there will be barriers. I thrive on that kind of stuff. Reporter: Unique risks. Look at the bottle caps. There's a lot of duct tape. We're duct-taping everything. Reporter: What does that do? My legs come off with a push of a button. And a lot of in the dance moves I smaek my legs together, so these are a makeshift fix. Reporter: Also risky and maybe a little risque, her costume last week. For me, costumes are an important part of the show. Derek's answer was, I'm not thinking about your legs. I'm thinking about what you would look great in. Let's go with that. Reporter: We got a sneak peek at the swing dance. Expect to see some lifts and that same indomitable spirit. Go, Amy, go. Be sure to tune in to "Dancing with the stars" tonight. The first couple will be eliminated. Tomorrow, on "Gma," we'll have that first booted couple and, a very special announcement. We always have very special announcements. That's coming up tomorrow. It's unbelievable to watch them dance. That's great. Quickly, a worldwide exclusive look now at "X-men,
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