Actor Joel Murray plays Freddy Rumsen, the man who got Peggy promoted in Season 1 then was forced out of Sterling Cooper because of his drinking in Season 2. He talked to AMCtv.com about musical zippers and wetting his pants, among other things.

Q: You're featured extensively in last week's episode "Sixth Month Leave." Do you have a favorite scene?

A: The scene after his pants-wetting incident when he goes into Peggy's office to check and see how everything went and tried to pretend like everything was fine -- I was pretty excited about that one. It's a wonderfully sad scene. The writing was just fabulous, kind of dark and humorous. There was something so simple about it that I liked and when we got done doing it the first take, I turned around and one of the costumer girls was crying. I was playing it in a way that I thought might be touching, but I didn't realize that somebody would be crying already. Maybe at the end of the episode I thought, but it tugged some heartstrings early.

Q: How did they manage to show Freddy wetting his pants in "Six Month Leave"?

A: My stand-in helped me quite a bit. He went through the testing and they tried all kinds of liquids as to what would show up best on a flannel pair of pants and look right. They ended up using rubbing alcohol, which kind of stings your privates basically. This guy was the guinea pig and told me what I had to do -- I was actually wearing a pair of Depends so I wouldn't get stung by the rubbing alcohol. I was hooked up to two strategically-placed tubes, and while I was doing the scene, a guy off-camera was turning a valve and it just kind of happened. Not something you get to do every day.

Q: Tell me about playing Mozart on your zipper in "The New Girl."

A: I had gotten the script and I knew the song. I'm a little musically inclined; I play the clarinet and the saxophone. So at home, just on a pair of jeans, I practiced it and could hear it actually sounding like something musical. And then you get to work and they give you a pair of pants with about an 18-inch zipper, so I had to re-tune for the new pants. Before we did the scene, the sound guy wanted to get a version of it, so I went into a stairwell that was very quiet and played the bit on my zipper for him and he was like, "Oh my God, you're actually hitting notes." He was shocked that I could actually play the song. The editor told me too, "It was actually on-key and you nailed it."