It’s not your average night out at a karaoke bar when Gerard Butler, Demi Moore and Michelle Monaghan drop in, but that’s what happened this weekend at Rockstarz in Detroit.

The A-listers are all in town filming and met up for a raucous singalong at the bar, belting out hits including Sheryl Crowe’s All I Wanna Do and AC/DC’s You Shook Me All Night Long.

Demi and Gerard have been friends since they visited Haiti together for Artists for Peace, and Michelle stars in Butler’s latest film, Machine Gun Preacher. Meanwhile Demi is in town filming LOL with Miley Cyrus – who may have been able to put the other three celebs to shame on the mike, but is obviously too young