I was on a podcast recently, talking about the craft of acting, when the host caught me off guard with a direct question.

He asked, “Alan, in all those years in the mud, what was the hardest you ever laughed while cameras were rolling?”

It didn’t take me a second to answer.

I didn’t have to search my memory.

The answer was instantaneous, and just thinking about it made me laugh right there in the studio.

It was during our third season.

We had a guest star coming in to play a completely unhinged officer named General Bartford Hamilton Steele.

That guest star was Harry Morgan.

This was long before he joined our cast permanently as Colonel Potter.

At the time, he was just coming in for one glorious, chaotic week.

Harry was a veteran actor.

We all grew up watching him in dramatic roles, so we expected a stern, serious presence on set.

And he was serious, right up until the director spoke.

We were filming the big court-martial scene.

Hawkeye is on trial, and General Steele is presiding.

The script called for Steele to be unpredictable, but none of us were prepared for the choices Harry was secretly about to make.

We were all in our positions.

Wayne Rogers was standing next to me.

McLean Stevenson was seated nearby.

The studio lights were hot, the soundstage was silent, and we were completely focused.

Gene Reynolds, our director, was watching the monitors intently.

We had rehearsed the blocking, but Harry had intentionally held back.

He kept his cards close to his chest.

He wanted to save the real performance for the camera.

The clapboard snapped.

Gene called out action.

The scene started normally.

Harry looked down at us from the judge’s seat.

He took a deep breath, and you could feel the energy in the room shift.

Something strange was about to happen.

You could see a mischievous glint in Harry’s eye.

The tension on the soundstage grew incredibly thick.

Nobody breathed.

And that’s when it happened.

Harry suddenly threw his head back, slammed his hands down on the desk, and burst into a completely unprompted, full-throated rendition of “Mississippi Mud.”

He didn’t just sing it.

He performed it.

He was shimmying his shoulders, bouncing in his chair, and delivering the lyrics with the wildest, most manic grin I have ever seen on a human being.

The script simply said General Steele loses his train of thought.

It did not say he turned into a vaudeville performer mid-trial.

For about two seconds, there was absolute, stunned silence in the room.

We were all trying to process what we were witnessing.

Then, the dam broke.

Wayne Rogers was the first to go.

He made this awful snorting sound, completely broke character, and had to physically turn his back to the camera so nobody would see his face.

McLean Stevenson just dropped his head into his hands, his shoulders shaking uncontrollably.

I bit the inside of my cheek so hard trying to maintain a straight face that I actually tasted copper.

I was determined not to ruin the take.

I was Hawkeye Pierce, I was on trial for my life, and I needed to look bewildered, not amused.

But Harry didn’t stop.

He kept the song going, and then he looked directly at me.

He locked his eyes onto mine, raised his eyebrows in time with the music, and gave me this subtle little wink.

That was it.

I was gone.

I burst into tears of laughter.

Gene Reynolds yelled cut from the darkness behind the cameras.

But even Gene couldn’t project any authority, because his voice was cracking.

He was laughing so hard he was physically coughing.

We had to take five minutes just to compose ourselves.

The makeup department came in to touch up our faces because we were all genuinely crying.

We got back to our marks.

We promised each other we would hold it together.

Gene called action again.

This time, Harry waited a little longer.

He delivered his lines perfectly, stared at us, and right when we thought we were safe, he did the shoulder shimmy again.

We completely fell apart.

Take two was ruined.

Take three was even worse.

By take four, the entire camera crew was compromised.

You have to understand, camera operators are trained to be completely still.

They are the silent observers of the set.

But during that fourth take, I looked over and saw the heavy metal camera literally vibrating.

The operator was shaking so hard from suppressed laughter that the frame was bouncing up and down.

The boom operator had to lower the microphone because his arms went completely weak.

It was a complete breakdown of professional television production.

And the absolute funniest part of the whole ordeal was Harry himself.

Whenever Gene would call cut, Harry would instantly stop singing.

He would fold his hands neatly on the desk and look around with this perfectly innocent expression.

He would ask, in his very distinguished, quiet voice, “Is there a problem, gentlemen? Am I doing something wrong?”

He knew exactly what he was doing.

He was playing us like a fiddle, and he was loving every single second of it.

We eventually had to shoot the rest of that scene by completely cheating our eyelines.

Whenever the camera was over Harry’s shoulder looking at me, I wasn’t actually looking at Harry’s face.

I knew if I looked at his face, I would laugh and ruin another take.

So I spent the rest of the afternoon delivering my lines to a piece of silver grip tape stuck to the wall about three feet to the left of Harry’s ear.

It was the only way we could get through the pages without crying.

When you watch that episode today, you can actually see the real strain in our faces.

We look like men who are in physical agony, and that’s because we were.

Trying to hold in a massive laugh when you are utterly exhausted on a soundstage is one of the most painful experiences in the world.

But that day changed everything for the history of our show.

When Harry finished his week and left the set, we all just looked at each other in awe.

We knew right then and there that we had to get him back permanently.

He had completely destroyed us, and we loved him for it.

When McLean eventually left the series, there was never really a debate about who should replace him as the commanding officer.

We all just remembered the man who ground production to a complete halt with “Mississippi Mud.”

It is funny how the unexpected moments that completely wreck a day of filming are often the ones that build the strongest bonds.

You really cannot manufacture that kind of genuine, uncontrollable joy.

What is the hardest you have ever laughed at the worst possible time?