I was recording an episode of my podcast a few weeks ago, having a relaxed conversation with a fellow actor.

Out of nowhere, my guest decided to turn the tables and become the interviewer.

He leaned across the microphone and asked me a question I had not thought about in years.

He wanted to know about the operating room scenes on MAS*H, specifically asking what was the absolute hardest I ever had to fight to keep a straight face while the cameras were rolling.

It took me two seconds to pull the memory up.

I started laughing before I could even formulate the sentence, my mind going straight back to Stage 9 at the 20th Century Fox lot in the early nineteen seventies.

People do not realize how incredibly hot those soundstages were back then.

We were constantly under massive, heavy studio lights that baked the room.

When we shot the operating room scenes, we wore heavy surgical gowns, face masks, and rubber gloves.

Underneath, most of us were in our underwear and combat boots just to survive the intense heat, but from the waist up, we had to look perfectly professional.

That brings me to McLean Stevenson, who played our commanding officer, Henry Blake.

McLean was a comedic genius with brilliant, natural timing.

But McLean famously hated memorizing his lines.

He viewed learning dialogue as a mild suggestion rather than a strict requirement.

Because the medical jargon was so dense, he would hide cheat sheets everywhere on the set.

He would tape them inside clipboards or stick them to the back of a nurse’s tray.

One afternoon, we were filming a deeply dramatic scene.

McLean had to deliver a massive paragraph of highly technical medical dialogue while performing surgery.

I watched him before the take, quietly setting up his cheat sheet.

He had found what he thought was the perfect hiding spot.

He took a piece of medical tape and attached his script right to the bare chest of the background actor who was playing the wounded soldier unconscious on the operating table.

The director called for action.

We started the scene, and McLean was doing beautifully.

He was staring intently down at the patient, rattling off these complex medical terms perfectly.

But something was shifting.

The intense heat from the studio lights was beating down on all of us.

I was standing right across the table from him, and I saw his confident expression start to falter.

A strange, awkward tension started building in his eyes above his surgical mask.

And that’s when it happened.

The background actor lying on the table was starting to sweat under the blazing hot lights.

He was sweating profusely.

The moisture on his chest caused the medical tape holding McLean’s entire monologue to completely lose its adhesive grip.

As McLean was mid-sentence, delivering this heavy, dramatic instruction to the nurses, the piece of paper began to slowly slide down the extra’s chest.

It was moving in agonizingly slow motion.

It slid off the damp skin, slipped quietly down the side of the surgical cot, and vanished completely into the dark abyss beneath the table.

McLean stopped speaking abruptly.

He was completely frozen in place.

His surgical mask covered his mouth, but his eyes were completely wide with absolute, unfiltered terror.

He looked up at me.

I looked back at him, holding my breath.

For a moment, there was just dead silence in the operating room.

Then, McLean tried to genuinely ad-lib the complex medical jargon to save the take.

He started spouting absolute, confident nonsense.

He pointed into the surgical cavity and yelled out for the nurse to hand him the shiny metal clamp thing to bypass the spleen artery tube.

I could feel my own chest tightening as I tried to hold in my laughter.

Wayne Rogers, who was standing next to me playing Trapper, realized exactly what had just happened.

Wayne simply could not handle it.

He had to physically turn his entire body away from the camera because his shoulders were shaking violently.

But the absolute worst part was the extra on the table.

This poor background actor, who was supposed to be completely unconscious and under deep anesthesia, heard everything.

He knew the script had fallen off his chest, and he heard McLean panic.

The extra started vibrating.

He was desperately trying not to move, but he was laughing silently, which meant his entire torso was shaking uncontrollably.

The dying patient was now visibly chuckling, and the movement was shaking the entire operating table up and down.

McLean realized he had completely lost control of the room.

He finally gave up the act, threw his bloody rubber gloves up in the air, and just stared blankly out at the director.

He looked down at the shaking extra on the table and declared to the room that we had lost the patient, because he had apparently laughed himself to death.

The director yelled cut, but he could barely get the word out.

He was laughing too hard to even pretend to be annoyed with us.

The entire crew completely erupted.

The camera operator had been laughing so hard that the camera was shaking, meaning the footage was completely unusable anyway.

Even the boom operator had to lower his microphone pole because he was laughing too hard to hold it steady overhead.

We had to completely stop production for the afternoon to reset the room.

It derailed the entire filming schedule.

Every time we tried to start the scene again, someone would look at the extra’s bare chest, remember the paper sliding away into the dark, and we would all start breaking character again.

We just could not get through it.

It took us nearly an hour to finally get a clean take of that one specific medical monologue.

In order to get the scene finished, the prop department actually had to write McLean’s lines in tiny letters on the inside of my surgical mask.

This meant that every time he needed a line, he had to lean uncomfortably close to my face and cross his eyes to read the dialogue off my cheek.

That, of course, caused an entirely new wave of laughter from the crew every time he leaned in.

It is funny how clearly that chaotic afternoon stands out in my mind all these years later.

We were making a television show that dealt with incredibly heavy, dark, and difficult themes.

The writing constantly asked us to process the deep tragedy of a medical unit working in a war zone.

But the secret to the show, and the reason we all survived the heavy emotional weight of the material, was the constant, ridiculous comedy happening just behind the scenes.

The humor was our ultimate survival mechanism.

We laughed together to keep from crying, and sometimes, a piece of slippery medical tape was all it took to completely break the tension of a long workday.

I would love to know how you handle stressful situations in your own daily life.

If you had to secretly hide a cheat sheet at your job to get through a tough day, where would you hide it?