In the new green band trailer for the apocalyptic comedy “This Is The End,” debuting exclusively here on Yahoo! Movies, the multiplatinum artist plays herself just hanging out at a massive party hosted by James Franco (also playing himself). That’s when Michael Cera (played by guess who?) gets a little forward, and Rihanna won’t stand for it.

At last weekend’s WonderCon convention in Anaheim, CA, star/co-writer/co-director Seth Rogen said that not only did Rihanna and Cera play themselves, they did their own stunts. Rogen and his cohort Evan Goldberg (they also wrote “Superbad” and “Pineapple Express” together) said Cera told Rihanna that he was actually going to smack her behind while cameras rolled. Then she told him she would really be smacking him in the face. And she did. Hard. Multiple times.

Watch Rihanna get tough (and then meet an unfortunate end) in the trailer for “This Is The End,” then keep reading to learn how Rogen got the superstar to play herself and what inside joke that he loved had to be cut out of the film.

So how did Seth Rogen get one of the biggest music acts in the world to join his movie? Well, it turns out, she’s a big fan. In an interview at WonderCon, Rogen told Yahoo! Movies the idea came from an interview he read with Rihanna several years ago. She was asked to name her favorite movies, and according to Rogen, “two out of the three of them were ‘Superbad’ and ‘Pineapple Express.’ I am so not used to seeing that that I literally just clocked in my head, ‘Oh, Rihanna is a fan of ours.’”

Evan Goldberg and Seth RogenEvan Goldberg and Seth Rogen (Photo: Photo by Araya Diaz/WireImage)As Rogen was writing the script where he and his buddies Jay Baruchel (who worked with him on TV’s “Undeclared” and “Knocked Up”), Jonah Hill (from “Superbad”), Danny McBride and Craig Robinson (both in “Pineapple Express”) are all partying at James Franco’s house when the world ends. Rogen said, “We just thought, ‘What if you had a bunch of famous people playing themselves in this completely ridiculous situation, basically, where they’re forced to be violent and bad [Laughs] and kind of show the worst parts of themselves.”

Rogen knew they would populate the party scene with many of the funny actors he’d worked with in earlier films, like Paul Rudd, Mindy Kaling, Aziz Ansari and Kevin Hart. Then, he said, it occurred to him, “At these parties there’s always someone who doesn’t belong there. It could be funny if, like, someone you don’t associate with us is there.” So he and his co-writer/co-director Evan Goldberg wondered if maybe Rihanna would do it. “And she was totally psyched to do it,” Rogen said.

Rogen did admit that writing roles for his friends where they would be basically playing themselves was harder you might think. He said, “I think we missed the mark on the first time out of the gate on a few of them, honestly.” He said in the early draft of the script the characters were a little too similar to how the actors had already been presenting themselves on-screen. “And I also think we weren’t sure what they’d be comfortable with until we sent them a script and started really having that conversation.”