Matt Damon: Kissing scene with Michael Douglas easier if he pretended it was Catherine Zeta-Jones

Matt Damon and Michael Douglas star in the upcoming movie "Behind the Candelabra," a biopic about famed entertainer Liberace. Douglas plays Liberace, while Damon plays his much-younger lover Scott Thorson.

Naturally, there were some kissing scenes between the two -- and Damon had a unique technique for them.

"Matt actually said to my husband that when he had to kiss Michael, he'd close his eyes and pretend he's actually kissing me, which I thought to be extremely flattering," Michael Douglas' wife Catherine Zeta-Jones tells Access Hollywood.

"When you have to make love or kiss on film, it could be a man, a woman, but it's always strange," Zeta-Jones continues. "It's not something that's an entirely normal day out at the office. I remember when I had to kiss Brad Pitt once, Michael asked me what I was doing that day. I went, 'I'm lying in bed, kissing Brad Pitt. He went, 'Good for you, darling. You enjoy.'"

"Behind the Candelabra" will be released later this year on HBO.