How the Kim Possible theme song became Christina Milian's biggest surprise hit

Christina Milian is here to tell you the sitch: no one, least of all her, expected the Kim Possible theme song to become a hit.

Back in 2002, the former host of Disney Channel's Movie Surfers was just beginning to launch her pop music career with breakout single "AM to PM," but she never forgot her roots. So when a Disney Channel exec called and asked her to record the theme song for an upcoming cartoon series, she immediately agreed. She thought it was your basic, average ... song.

"I didn't think anything of it," Milian tells EW. "I had come out with my first album and was touring overseas, but I had this relationship for like three years with Disney — I had been doing that before I became an artist, before I'd become known with my record deal. Of course I would say yes, that was my past and that's who helped build my career."

The song was already written — Milian still wishes she could have collaborated on that part of the process but she was too late — so she went straight into the recording studio despite not knowing much about the series. "We didn't know how big it would end up being or even what the show would end up being," she says. "To me, I'm just singing a theme song on a cartoon and there's lots of cartoons that are out there. But I didn't know what it would become. I'd only seen a picture of the character, I didn't even get to see her in movement so it was in the early stages of what it was."

Milian's own record label didn't even take the project seriously at first. "They like were like, 'Oh yeah, go ahead, go do this Disney song or whatever,'" she remembers with a laugh. "But then it really became a thing."

"Call Me, Beep Me!" was released as a single and played constantly on Radio Disney, and Disney Channel filmed and released a music video of Milian recording the song in the studio. "So even if Kim Possible wasn't playing, this was playing between every single show that you watched on Disney," she says, recalling how her mother was her stylist back then and she was forever immortalized on camera in a red Juicy Couture hoodie with her name on the back. "It was definitely of the time," she jokes.

The theme song had taken on a life of its own — and soon her record label looked at with a new appreciation. "It really came at a great time when my music was coming out and doing well and then here you have this other song that they didn't even have to worry about, it was a Disney song so Disney was pushing it," Milian says. "They were watching it rise on the charts and all of a sudden, they're showing off, telling everybody about this record that they didn't necessarily have anything to do with it, but they're proud."

And 20 years later, people still ask Milian about this song more than anything else, which is why she's not shocked that it landed on EW's ranking of the best TV theme songs of the 21st century. "I never thought I'd still be talking about this song after all these years but I still have people come up to me, definitely millennials but also people younger and older, who all still connect with it," she says. "People back then and even now still use it as a ringtone." She hums the iconic four beeps before adding, "It's so catchy!"

But Milian still finds herself having to clear up some confusion. "I'm not Kim Possible," she says with a laugh. "Sometimes people think that I am Kim Possible. I'm only the theme song singer. Or they mix it up the other way and think Christy [Carlson Romano], which is the actress who plays Kim Possible, is the one that sings the song. People are still surprised by that." Also, she warns younger fans, absolutely do not ask her what "beep me" means: "They better not, I'll feel so old!"

A version of this story appears in the February issue of Entertainment Weekly, on newsstands now and available to order here. Don't forget to subscribe for more exclusive interviews and photos, only in EW.

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