Jack Black has admitted it was "intimidating" visiting a high security prison to prepare for his latest movie role.
The Hollywood funnyman went to the jail to meet convicted killer Bernie Tiede, who he portrays in Richard Linklater's film Bernie.
The star told E! News: "It was scary. It was intimidating...Yeah, we're safe because there are guards around, but you don't feel safe."
He added: "You feel like you can get killed any minute."
The film follows a local undertaker who murders his rich widow friend.
Jack will share the screen with Shirley MacLaine and Matthew McConaughey in the movie, which is due to be released in the US this month.