Call this the worst secret kept in Hollywood.

"Cougar Town" star Busy Philipps appeared on Bravo's "Watch What Happens Live" on Wednesday, and was honest when a viewer asked who the biggest stoner was on the set of NBC's "Freaks and Geeks." Philipps starred in the now beloved comedy series alongside Seth Rogen, James Franco, Jason Segel and Linda Cardellini from 1999-2000.

Though host Andy Cohen initially guessed James Franco, Philipps said that Franco doesn't do pot, and revealed that it was actually Rogen who used to provide her with weed.

"Yeah, I would say Seth," she shrugs. "He used to give me my pot, so ..."

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According to the 35-year-old actress, it was high quality product.

Rogen has been open about his marijuana infatuation before, even offering to be rapper Waka Flocka Flame's personal blunt roller in September.

Waka Flocka Flame then posted a photoshopped pic of him and "The Interview" star sharing some weed, writing: "First day on the job @SethRogen @3BRICKHOUSE #icanROLL."