After attending the screening of the film, the celeb group met up at the infamous Chateau Marmont hotel, reported Us magazine.
They then travelled in Bieber's USD 200,000 Mercedes Benz minivan to celebrate the opening of actor David Arquette's new nightclub, Bootsy Bellows.
Despite 18-year-old Bieber and Gomez, 19, being under the legal drinking age in America, the couple enjoyed the evening out with Pattinson and Perry.
"Rob and Katy are good friends so he was happy to celebrate with her, it wasn't just the four of them, but everyone was close," a source said.
Apparently "Twilight" star Pattinson has been keeping in touch with Perry after her divorce from Brand last December.
