Just when you think you were becoming accustomed to the tear-jerking charms of "This Is Us," along comes Gerald McRaney to give you yet another great big cry.

NBC's first-season supershow pulled out all the stops in its flashback-only episode "The Big Day," which not only fills in some poignant details around the birth of Jack and Rebecca's babies but also offered a moving showcase for TV vet McRaney ("Simon & Simon," "Major Dad," "Deadwood," "House of Cards") with a storyline featuring the increasingly recurring physician Dr. Nathan Katowsky.

Dr. K is growing more vital to the Pearson clan's history, and, as McRaney tells Moviefone, the role is just what the doctor ordered.

Moviefone: How lovely to learn the extent of Dr. K's backstory.

Gerald McRaney: It was obvious in the pilot how close Dr. K was to his wife. So they just embroidered that quite a bit. It's a lovely, lovely backstory. I love how the whole theme of it gets so wonderfully woven, and everyone is now moving on with their lives. In spite of bad things happening to them, they're moving on.

The thing I love about this whole show is that there are no bad people in it. It's all good people, overcoming some bad things, but they're all good people. These are people that I want to sit and have coffee with.

Was there a moment or a scene where you choked up or that you had difficulty with?

A couple of them, yeah ... It's just imagining losing my wife, and where that would put me, and you're there. It's not a very pleasant place to go.

Do you have any advance word that there was going to be an episode like this, with such a wonderful acting opportunity for you?

No. I wondered who I had to pay off, basically, for writing such a great role. This is phenomenal writing. It's a gift for an actor to play stuff like this. Keep this under your hat, but this stuff I would do for free.

When you shot the pilot, you couldn't know how big this whole thing would blow up. What was your reaction after the show premiered and critics and audience loved it?

Primarily, that they wanted me to come back and do more -- I had no idea what happened. This was a guest star role on somebody's pilot, and to be invited back several times now is really a nice compliment, and a treat.

That's the other thing about working on this show: It is populated by the same kind of people that their characters are. Everybody who works on this show, they're just great people. They've got phenomenal talent, and there's not a prima donna in the whole cast on up. It's a very pleasant place to work.

When you hear from the viewers who have embraced this show and just feel so warmly about it, what that's like for you to be able to interact with the fans of the show?

I got an email from a friend of mine, a lady that I'd gone to high school with who said, "This is the kind of doctor everybody wants to have. This is the man you want to go to if you're sick, if there's something really wrong with you; you want that guy talking to you."

And that's been basically the kind of response that I've gotten. The other night I was out to dinner and a couple stopped me on my way out to tell me how much they like the show. I was very complimented. The gentleman said, "I'm a physician, and you brought so much humanity to that doctor." So that was nice.

Everything is pretty much along those lines. I think people are gratified that there's such a positive show on the air.

What was it like seeing this episode? Your performance is so crucial.

It's a little frightening, quite frankly. I don't like looking at myself. I never have. All these people here, so good. Phenomenal. The young lady who played the fireman's wife is somebody that I recommended. She and I did a play together in New York several years ago now -- Virginia Call. She's just terrific. I was so pleased. I felt a little like her dad, looking up there and saying, "My kid did good."

Did you ever have a doctor like this in your own life?

Yeah. Yeah. I did. The whole time I was growing up. He was this kind of doctor who didn't just examine you and send you off to somebody else to do the lab work and this, that, and the other thing. He sat and he talked with you. He was the doctor, took care of stuff. And you felt when you went to him, everything was going to be OK.

You've had a lot of great roles on a lot of great shows over a lot of years. Where does this one rank?

Right at the top. Right at the top. The writing -- that's what starts everything for me is good writing. If the writing is good, then it's fun to work on. Like every actor, I've done stuff to pay the rent, with bad writing. There's just no comparison. This sort of thing is just a joy.

It doesn't matter the particular style that a good writer has. Good writing is good writing. And whether it's Dan Fogelman, whether it's David Milch, it doesn't matter. The quality is what matters, not the style of it. Styles, they change. But the quality of writing, and it's the humanity of the writer that makes it happen.

"This Is Us" airs Tuesdays on NBC.