NEW YORK -- Sean Penn made a smoky appearance on "The Late Show with Stephen Colbert" to promote his book.
The actor told the host Monday he had taken a sedative "to get to sleep after a red-eye flight" and Penn lit a cigarette.
The two-time Academy Award winner described his novel, "Bob Honey Who Just Do Stuff," as "the conversation once a year with the drunken uncle."
Penn lit a second cigarette and Colbert asked him to consider quitting. Penn said it was "job security for oncologists."
Meanwhile, Penn told comedian Marc Maron in a podcast that that he and his ex-wife Robin Wright "don't have a lot of conversation."
Penn said they "have very separate relationships" with their children, 26-year-old Dylan and 24-year-old Hopper.
The couple divorced in 2010.
