Host: Alan, you’ve talked a lot over the years about the camaraderie on the set of MASH, especially during those grueling summer shoots in the Malibu hills. But when you look back at the early seasons with McLean Stevenson, what is the one moment that still makes you laugh out loud just thinking about it?

Alan Alda: Oh, wow. McLean. You know, people don’t realize just how much of a comedic spark plug he was for all of us. When the cameras were rolling, he was brilliant, but when the cameras stopped, or even when they were just resetting, he was constantly looking for ways to keep our spirits up. We were working fourteen-hour days in those heavy military uniforms, sweating under the lights, and sometimes the energy would just plunge.

Host: So he was the resident prankster?

Alan Alda: Absolutely. He couldn’t help himself. There was this one particular afternoon during the second season. We were filming inside the main office set. It was a terribly hot day, even inside the soundstage. The scene itself wasn’t supposed to be funny at all. It was one of those moments where Henry Blake had to read a long, tedious bureaucratic notice from the army high command to Hawkeye and Trapper.

The director wanted to shoot it as a single, continuous take from the waist up to save time. The crew spent about forty minutes setting up the lighting, getting the angles perfect. McLean was sitting quietly behind his desk, looking remarkably serious, just staring down at his script. Wayne Rogers and I were standing opposite him, trying to stay in character.

The whole stage went completely silent, which was incredibly rare for our set. You could hear a pin drop. The director called for action, and the camera slowly started to track in close on McLean’s face, capturing his somber, weary expression.

And that’s when it happened.

Alan Alda: As the camera pushed in, McLean started reading the lines beautifully. He had this perfectly somber, authoritative voice going. But Wayne Rogers happened to glance down just a bit to the side of the desk. I saw Wayne’s eyes go incredibly wide, and his jaw just dropped. So, naturally, I looked down too.

McLean had completely taken off his uniform trousers. He was sitting behind that desk in his full military tunic, tie, and officer’s hat from the chest up, but underneath, he was wearing these bright, ridiculous, silk polka-dot boxer shorts. His bare, hairy legs were crossed, and he was casually swinging one foot back and forth, all while delivering this deeply serious speech about army regulations without blinking an eye.

Host: Oh no. He didn’t.

Alan Alda: He absolutely did. And you have to understand, Wayne and I were supposed to be reacting with grave discipline. Instead, Wayne let out this high-pitched snort. I tried to cover my mouth, pretending I was coughing, but my entire body was shaking. We were biting the insides of our cheeks so hard they were practically bleeding.

Meanwhile, McLean just kept going. He didn’t break character for a second. He looked right at us with this intense, commanding stare, lecturing us about military protocol, while his bare legs were fully on display to anyone standing where we were standing. The contrast was just lethal.

Host: Did the director notice right away?

Alan Alda: No, that was the best part! The director, focusing his view on the small monitor, only saw McLean from the chest up. On the monitor, it looked like an Emmy-winning dramatic performance. So the director is looking at the monitor, then looking at Wayne and me ruining the take, and he is getting furious. He finally screams, “Cut! Cut! What on earth is wrong with you two? We are trying to wrap this scene!”

The director stormed onto the set, marching over to lecture us about professionalism. Wayne couldn’t speak; he just pointed weakly at the desk. The director followed his finger, looked over the desk, and stopped dead in his tracks.

Host: What did McLean say?

Alan Alda: McLean didn’t even drop the character voice. He looked up at the director, totally deadpan, and said, “What? It is ninety degrees on this stage, the camera is only framing me from the nipples up, and my lower half is completely civilian. I am simply practicing efficient thermal management.”

The moment he said “efficient thermal management” with that straight face, the entire soundstage just erupted. The camera operator laughed so hard he accidentally knocked his headset off. The script supervisor was bent double. Even the director, who had been ready to bite our heads off, just threw his hands in the air and started howling.

Host: Did you manage to finish the scene after that?

Alan Alda: Eventually, but it took us twenty minutes just to stop crying. Every time the director called action, Wayne or I would look at McLean’s face, remember what was happening under that desk, and immediately break down again. We ended up having to put a piece of cardboard on the side of the desk just to block our view of his legs so we could get through the coverage.

It became this legendary running joke on the set. From that day on, whenever anyone had a close-up behind a desk or a table, the first thing the rest of the cast would do was sneak around to see if they were actually wearing pants. More often than not, thanks to McLean’s influence, someone wasn’t.

Looking back, those are the moments that made MASH what it was. We dealt with a lot of heavy, dark themes in the scripts, and the only way to keep the show grounded was to have that kind of absolute, irreverent absurdity behind the scenes. McLean understood that better than anyone. He knew exactly when we needed a break from the tension, even if it meant sacrificing his own wardrobe dignity.

Do you have a favorite behind-the-scenes tradition from a show you love?