Bill Murray is so out of touch with today's young stars and reality TV celebrities he doesn't know who they are when they say hello.
The actor tells Black Book magazine he was recently caught out when Josh Hartnett chatted to him about working with his ex-girlfriend Scarlett Johansson on Lost in Translation - because he had no idea who the Black Hawk Down hunk was.
Murray says, "This guy shakes my hand and says, 'You worked on Lost in Translation with my girlfriend. Was she as much trouble for you as she was for me?' But Scarlett was 17 when I worked with her, so no, she wasn't."
The movie veteran insists he's not trying to be rude but he just doesn't know anyone these days.
He adds, "I go through (magazine) Us Weekly, and it's filled with reality TV stars I've never heard of. I don't recognise anyone."