“Sean doesn’t care at all what people think,” a source tells PEOPLE. “He likes controversy and debate and doesn’t mind shocking people.”
While promoting his new novel Bob Honey Who Just Do Stuff, the 57-year-old actor smoked two cigarettes on-air and admitted to Colbert that he had taken a sedative before the interview began. “I’m doing well. You’ve inherited a little of the Ambien I had to take to get to sleep after a red-eye last night,” Penn remarked.
“So in other words, you’re still a little bit on the Ambien train right now?” Colbert asked before the two-time Oscar winner responded, “A little bit.”
Later on in the interview, when the late-night host advised the actor to “please not smoke anymore,” Penn joked that his smoking habit was good news for doctors, calling it “job security for oncologists.”
According to another source, “Sean is a one man band, always has been. He loves the fight.”
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While the actor’s first fictional book Bob Honey Who Just Do Stuff is an expanded version of his 2016 audiobook of the same name, Penn’s made a few new controversial additions to the story.
In one passage, he seems to take aim at President Trump. In another, he references the #MeToo movement while namechecking Louis C.K. and Charlie Rose as men negatively affected by sexual harassment allegations against them.
Bob Honey Who Just Do Stuff is now available for purchase.