Mariah Carey crashes Schitt's Creek's commencement video to sing 'Hero' with cast

There's only one person David Rose would ever allow to interrupt him while he's singing his songs, and that person just so happened to crash the Schitt's Creek commencement video for the class of 2020. Mariah Carey joined Dan Levy, who plays David, and the rest of the cast to sing her song "Hero," and it was a treat.

The actors from the hit Canadian comedy reunited on Sunday to celebrate this year's graduating class while in character, and they were their usual extra selves. Moira (Catherine O'Hara) confused everyone with her vocabulary (e.g., "panegyrical"), David and Alexis (Annie Murphy) were dramatic, and Stevie (Emily Hampshire) seemed over it. Patrick (Noah Reid), Twyla (Sarah Levy), and Johnny Rose (Eugene Levy) were also part of YouTube's "Dear Class of 2020" virtual commencement celebration.

The cast began singing "Hero," which David chose, of course, and toward the end, Carey showed up to finish the classic track off strong with Schitt's Creek's finest. And like a true diva, her hair was blowing gracefully from what we assume was a wind machine, just out of frame.

"Moira, darling, I hope you didn't mind that I jumped in like that. You all sounded so good that I had to get in on it," Carey said after they finished singing.

Everyone looked happy and surprised to see the songstress, but David was on a whole other level.

"I think I'm having a heart attack," he said.

In the video, Carey delivered a sweet and funny message for teachers, whom she thanked for dealing with "students like me, who never really showed up at school on time."

Then David fainted after Carey serenaded him personally.

Carey's music holds a special place in Schitt's Creek canon, as Noah first told David he loved him by saying, "You're my Mariah Carey." The singer even retweeted the touching clip last year and encouraged people to watch the show. The critically acclaimed series, which followed the disgraced Rose family's comeback journey, ended this April after six seasons.

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