The leather-clad tough guys who rescue Eric Stonestreet and Jesse Tyler Ferguson's stranded characters in Tv comedy Modern Family's Australian special were real-life members of a hardcore biker gang.

Stonestreet admits he thought they were extras and started to chat to the gruff guys between takes.

He says, "I said, 'So, what do you guys do for a living?' And one guy in the back, he goes, 'What do you mean? We sell drugs!'

"We come to find out they're, like, these bikers who have been kicked out of Queensland in Australia and there's no more bikies (sic) allowed in certain areas of the country."

And the biker gang almost landed producers in trouble, were it not for an eagle-eyed Stonestreet.

He tells U.S. chat show host Jimmy Kimmel, "One guy, I took a sneaky picture of his helmet and I went over to our producer, who is a Jewish fellow, and said, 'Danny, we may need some black duct tape and (block) out this swastika on the biker's helmet.

"Other than that they were so nice - one was a vegetarian, one was anaemic, the other one was scared of heights..."

The Modern Family Australian special aired in America last week (23Apr14).