"If you're a 'stand-in' they just want your body. If you're the same height as an actor they use you to set up their cameras and sound equipment ready for the next day and they don't have to pay you as much as they'd have to pay an actor. I'm in the Peter Rabbit movie that's on at the moment," he said.
While Russell enjoyed working as a film extra he agreed there was a lot of waiting around.
"That's where these smartphones are good. You can just read things on your phone while you're waiting but you've got to make sure they're out of sight when you're on the set.
"There are a lot of rules you have to follow like no talking and never ever look at the camera. It's very organised.
"The meals they gave us were great. First of all the actors get fed, then the crew and last of all the extras. We really were 'bottom feeders' but they were great meals.
"I don't know if they want me for an extra for this movie. They liked the fact that I've got a beard and it'll grow more in the next two weeks. There were some guys there who had really long beards."
In the meantime Russell is enjoying rehearsing his role as Hedley Planter the undertaker in Shenanigans Wake at Repertory Theatre which will open in late May.
"What did you think of that scene I do with Pat where we're both drunk and singing Danny Boy?" he asked.
"Funny", I replied. "It's really very, very funny."
