'Wizards Of Waverly Place' Inspired Billie Eilish's "Bad Guy" & Selena Gomez Just Found Out

Before Selena Gomez entered the music scene full-time, she played a wizard named Alex Russo on Disney Channel's hit series Wizards of Waverly Place. Fans loved to see her spunky character get into trouble each episode, and then try to fix everything with a bit of magic. To go along with its magical theme, the show had a catchy theme song called, "Everything Is Not As It Seems." Apparently, the Wizards Of Waverly Place theme song was so good, it inspired Billie Elish's "Bad Guy," and Gomez had no idea until now.

As Eilish's fans know, the 18-year-old singer is a huge fangirl, as she's previously admitted her love for Justin Bieber, Avril Lavigne, and Drake. Gomez can now be added to that list because, while appearing on The Tonight Show Starring Jimmy Fallon, the host told her she inspired Eilish's Billboard No. 1 single, "Bad Guy."

Gomez appeared on the show to promote her third studio album Rare, which Eilish's brother and collaborator, Finneas, helped produce. "We finished up ['Lose You To Love Me'] and gave him the song to produce it himself and he did an amazing job. He's obviously extremely talented."

Fallon then told Gomez she influenced Eilish and Finneas to record "Bad Guy."

"I don't know if you know this, but you have something in common with Billie," he said. "You're an inspiration for the song 'Bad Guy.'"

"Am I the bad guy?" Gomez hilariously asked, prompting Fallon to explain the Wizards of Waverly Place theme song inspired the song's hook. "I love Billie," Gomez said.

Fallon then played "Everything Is Not As It Seems" and Gomez couldn't help but feel embarrassed about it, since she recorded it over a decade ago. "Oh no," Gomez said, before the audience surprised her with a spontaneous sing-along sesh. Fallon also played "Bad Guy" for comparison and Gomez remarked how "cool" it was the songs sounded so similar.

Watch Gomez's reaction below around the 4-minute mark.

Eilish and Finneas talked about the song's similarities in a December 2019 Rolling Stone video. "You know what it literally is? It's not at all the same melodies, but it's literally 'Plants Vs. Zombies,'" Eilish said, referencing the 2009 video game. "And Wizards of Waverly Place," Finneas added.

Hear their comments near the 6:28 mark below.

Once again, Eilish proved just how big of a fangirl she is, and it's clear her idols appreciate her admiration.