Cedric Yarbrough posted a lengthy takedown of the singer on Facebook Wednesday night, after Ferrell confirmed her cameo in the film -- where she would have played herself -- was left on the cutting room floor.
"Okay since Will Ferrell is talking, I'ma talk-ing," he started his post. "Yeah, a real funny cameo was SUPPOSED to happen in the new film #TheHouse with the superstar Mariah Carey. But it was ruined by superstar Mariah Carey."
"The film takes place in a suburban home but is made into a 'Casino'. Why not have Mariah be an act in the casino? Funny idea," Yarbrough's post continued. "It's rumored that she eventually showed up to set. This is true. But after waiting for her for 3-4 hours! While we waited the director & team had the idea of doing a stunt that Mariah's body double would do now & bring in Mariah to match it. They do the stunt. All goes well. When Mariah finally showed up she refused to match the stunt. 'Darling, I would never do it that way...'. I heard her say those exact words."
But it didn't stop there.
"She then requested a large fan for her hair to be blown around and a camera that would be above her, basically a crane shot. This lady was unprofessional & borderline abusive to our director, who tried his best to appease her every wish," he went on. "In the acting community, it's not very good form to 'tell' on your fellow actors. They could be having a bad day, going through some personal things, & maybe Mariah was, I don't know. But I do know that our crew didn't deserve that, our director didn't. Hell, I'd just come off shooting 10 HOURS on 'Speechless' just to get there and wait. This kind of behavior just isn't cool."
According to Yarbrough, that wasn't even the "worst part," but he didn't elaborate. As for what young actors can learn from her alleged behavior, the "Reno 911!" alum added this: "Be on time, know your homework, but be courteous and respectful. For us old heads, the same. This kind of behavior should be called out for what it is. I miss 'I had a vision of love' Mariah. Be a damn professional."
Fellow co-star Rob Huebel also laid into Carey's supposed antics, calling it just "bananas."
As for Ferrell, he was very careful with his words on "Late Night with Seth Meyers" -- the Mimi talk starts around the 2:45 mark.
A rep for Carey wasn't immediately available for comment.