Kathy Griffin is well aware not everyone is a fan of her comedy… especially the celebrities she's notoriously made fun of!
But after endless encounters with Hollywood's elite over the years, the 56-year-old has revealed some celebs have been just downright MEAN to her face!
In her new book Kathy Griffin's Celebrity Run-Ins, the Emmy-winner recounts various moments she's had with over 125 stars, and not all of them are as pleasant as you'd expect!
Related: Kathy Dishes About Longtime Feud With Ellen DeGeneres!
One of the most shocking revelations from Griffin's latest exposé is that Jon Hamm might not be super charming 100% of the time — at least not when rubbing elbows with a comedy veteran.
The comedianne writes of the Mad Men star: