Whether it's a YouTube video of a sassy golden retriever doing the merengue, or a razzle-dazzle border collie shimmying to the beat on "Britain's Got Talent," diehard fans from Texas to Tokyo can't get enough of a playful but serious brand of global dance competition called "Canine Freestyle."
While it's undeniably fun to watch dogs dance, some say it's even more fun to do it yourself. It's a good bet most weeks of the year that prancing pooches and their proud owners are duking it out in a friendly canine-freestyle competition not far from your neck of the woods.
But the grande dame and, yes, Top Dog, of canine freestyle was a title long held by the graceful Carolyn Scott and her irrepressible golden retriever, Rookie. They were the Fred Astaire and Ginger Rogers of this world, and, like those stars of the silver screen, they kept things free and loose.
The key, Scott said, is improvisation, which goes both ways.
"With freestyle, it opened up the door for me to being very creative, into teaching Rookie behaviors no one had ever seen before," Scott of Jersey Village, Texas, told "20/20."
"Rookie actually had a say in everything I choreographed. We'd start the music, I had planned maybe one spin, and the next thing I know he'd go spinning across the room."
Rookie and Scott's pioneering dance moves, like the "Rookie Moonwalk" and the "Rookie Boogie," require the dog to complete complex backward and circling movements around his human partner. The moves are now classics emulated by countless devotees of the sport, all around the world. Rookie and Scott made it big, but became even bigger when their feisty rendition of "You're the One That I Want" from "Grease" hit YouTube, and racked up nearly 7 million hits.
But despite the fame, hardly anyone knew Scott and Rookie's real ballet, the story of how a human and a canine, imperfect in their own ways, taught each other how to overcome adversity.
Scott's story began in 1950s Texas, when the polio virus was sweeping through America, causing muscle-wasting in the limbs of hundreds of thousands. Young Scott recuperated in a polio ward, and when she was discharged, one of the muscles in one of her legs had shrunken significantly. After spending long periods in quarantine, the effect on her was profound.
"I was very shy. I did not go out a lot," Scott, 65, said.
Only with her grandmother did Carolyn truly feel free to be herself, she said.
"We'd turn the radio on, I would dance or sing," she added. "I just was amazed at her patience. She just loved me no matter what."
Four decades later, Scott found someone else to fill her grandmother's supportive role, and he had four legs.
"This little yellow dog taught me about being spontaneous and to enjoy life at a different level," bringing out a personality in her that she never knew existed, Scott said.
With Rookie, the feeling was mutual, Scott believes.
"I think I brought him to his full potential, and he helped me come to mine," she said.
Dozens of competitions and freestyle awards later, the pair seemed inseparable, making the rounds on "Regis and Kathie Lee" and "Good Morning America," and delighting millions with moves that looked simple on the screen, but demanded hard work and dedication.
It was a process that formed a tight bond between canine and human that freestyle dancers say you have to experience to truly understand.
"Carolyn and Rookie moved as one," said fellow canine freestyle competitor Pam Martin, who is also a multi-sport dog trainer and the owner of Top Dog Obedience Training School in Garland, Texas.
"Their bond and experience together caused them to move as a united force. If Rookie moved, Carolyn responded. And vice versa… Just like a couple who has been dancing for so long," Martin said. "A slight touch, a look, a glance… Rookie smiled and looked up to Carolyn and knew it was the best time of the day. It was the best time of the day when they got up and danced. People can spend all their lives trying to get that connection, human, dog, or otherwise and Carolyn and Rookie had that special something."
Sadly, about five years ago, Scott and Rookie's amazing ballet entered its final act. Rookie was diagnosed with cancer, dying in July, 2008 at the age of 15.
"That last year, I just took off. ... We spent it together," Scott remembered.
"I tried to slow everything down and enjoy each and every moment we had together," she said. "So again, he was teaching me, even at the end. He just loved life. He was an eternal puppy."
Watch the full story on "20/20: Pet Crazy," Friday at 10 p.m. ET.