Not long after Harry Wayne Casey founded KC and The Sunshine Band with some of his musician friends in the 1970s, he knew he was becoming a part of something groundbreaking. As an interracial R&B group, KC and The Sunshine Band had a unique place in the music industry, and their disco songs inspired a dance revolution. With hits like "Get Down Tonight" and "(Shake, Shake, Shake) Shake Your Booty," the group sold 100 million records worldwide -- they even became the first group to have four No. 1 pop songs in a single year (1975) since the Beatles.
During the height of their success, however, Casey struggled with his loss of anonymity, as he tells "Oprah: Where Are They Now?" in the above video.
"The reaction for us, to me, felt like Beatlemania," he says. "It was crazy with us. I mean, there would be 5,000 people outside of our hotel everywhere we went. I couldn't go anywhere."
While fans were clamoring to get close to the star, Casey felt more alone that ever.
"People say, 'Well, wasn't that exciting?' For me, it was the most loneliest time of my life," he says. "I remember just looking out of my hotel window down into that crowd and wishing that I could just stand in the middle of them."
Even thinking about that loneliness and pain 40 years later makes Casey emotional.
"I really wanted to go there; I wanted to be a part of it. And, for some reason, I didn't feel a part of it," he says, wiping away tears. "Sorry. I've never gotten that way before."
The isolation was too much to bear. "I just wanted out," Casey says. "I started taking prescription drugs... I just started partying."
Following his struggle with addiction, Casey reunited KC and The Sunshine Band in the '90s. "I've been touring all over the world," he says. "We've now recorded a new album... 'Feeling You! The 60s.'"
In the decades since his initial rise to fame, the 64-year-old frontman has come to view his experience in the entertainment industry through a wider lens.
"It's taken me 40 years to understand who Casey of KC and The Sunshine Band is," he says. "I know that my music has brought a lot of enjoyment to a lot of people. We all have purposes here on earth. That's one of my purposes. My purpose was to bring joy into people's lives, and I'm so glad that God used me as His tool to help facilitate that."
"Oprah: Where Are They Now?" airs Sundays at 9 p.m. ET on OWN.
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