When you’re filming a movie called ​Drinking Buddies ​—a movie that’s set in a Chicago brewery—it’s kind of inevitable that you would have a couple of many beers. But Olivia Wilde recently revealed that she (along with her other co-stars Anna Kendrick, Jake Johnson, and Ron Livingston) wasn’t just buzzed, but buzzed in a way that only tailgate participants and college students can get away with—starting in the early morning hours until late at night.

“We were hammered the entire movie because it was real beer, because beer on that set was cheaper than water,” she told Digital Spy.

She then recalled how Kendrick joined the set to film her scenes two weeks after production began, where the uninitiated star—before realizing it was real beer—took a huge gulp of the brew.

“She was like, ‘What’s happening? What are you guys doing?’ and we were like, ‘Oh, we forgot to tell you—the beer’s all real and everyone’s drunk. It’s 10am. Welcome to Drinking Buddies.'”