Sally Wingert and Mark Benninghofen are not a couple, but they play one on stage. A lot.

“Somebody asked me how many times we’ve worked together and I said, ‘Four.’ ” Then I went, ‘No, five. Wait, six. Seven,’ ” says Wingert.

The latest — however many that might be — comes Saturday, when “A Little Night Music,” the Stephen Sondheim/Hugh Wheeler musical, opens at Minneapolis’ Theater Latté Da, which paired them in 2015 for Sondheim’s “Sweeney Todd” and two years later in “Six Degrees of Separation.”

Wingert plays Desiree Armfeldt, an actor in Sweden, circa 1900. Tired of touring, she dreams of settling down, which feels possible when she becomes reacquainted with a former lover, Fredrik (Benninghofen), at a party, along with his new wife.

Multiple complications — and Sondheim’s biggest hit, “Send in the Clowns” — ensue.

On their intertwined careers:

He: Some of it was so long ago, at the Guthrie in the early ’80s.

She: In “Cyrano,” but we weren’t a couple. There was “Diamond Cut Diamond” at the [defunct] Cricket.

He: The guy wrote one play and we did it and it will never — Lovely play. Never heard of it since.

She: There’s “Juno and the Paycock” at the Guthrie, where there was an intimation that our characters were a little sweet on each other. That was Joe Dowling’s last show. And “Shooting Star” at Park Square.

He: Two people in an airport running into each other after 25 years.

She: We kissed for like 20 minutes. I’m telling you, it was the longest makeout-y thing I’ve ever experienced in a play.

He: Middle of the night ...

She: Snowstorm ...

She: Staff is gone, we’re there, we decide to give it a whirl and then we realize it’s ...

She: ... not going to happen.

He: It was about as much making out as you can do on stage, dressed.

She: And we went from that to “Sweeney.”

On the terror of singing on stage:

She: The special gift of working with Marky Mark is we’re in very choppy waters for us. These people in the cast are vastly more skilled and gifted in this musical milieu than Mark and I. We are really innocents abroad.

He: “Sweeney Todd” was the first musical I’d ever done and I’m 57. I’d been an Equity member for 35 years. Long story short: We wound up eyebrow-deep in a big Sondheim play and I don’t know what I’d have done without Sally.

She: Same. His musical load in this is huge. Mine, the part was written for Glynis Johns and Glynis wasn’t really a singer. So, thank God, right, for small favors?

He: She’s got “Send in the Clowns,” though, which is the one thing anyone knows from the show. And she’s wonderful.

She: It’s not just the singing, luckily. This has a lot more book than most musicals and that’s where Mark and I hit our comfort zones: telling a story through dialogue.

He: It’s a big learning curve. Sally and I don’t even know what page we’re on and the others are asking about whether they should change a natural to a sharp or whatever.

She: “Should we do a sforzando there?” What? [She erupts in giggles.]

He: They have that whole vocabulary and it’s just remarkable.

On the shorthand they’ve developed over three decades:

She: I don’t think it makes it easier to be A Couple. We’re just friends and it’s easier to work together as friends.

He: It takes out of the game that usual first week of not really knowing how each other operates.

She: With our characters, I think the sex is lovely but the friendship is even more gorgeous. They laugh easily, they speak easily, they’re peers and I think she falls like a hammer for him when they re-meet.

He: Within a page and half of the reuniting scene, there’s humor, whimsy. It’s very easy and comfortable, which is a real metaphor for the first day of rehearsal for Sal and I.

On director Peter Rothstein, whom Wingert says “has better taste in the theater than anyone I know”:

She: I get tons of notes from him that are really good. “Send in the Clowns” — before that song, Fredrik has a paragraph telling me how much he loves me, how fabulous I am, but then — that when his eyes are open, he wants to be with his young wife.

[In rehearsal] I was playing, really obviously, the delight in how much he likes me, which made the “but” more crestfallen. That’s what Sally thought.

Peter said, “Don’t do that.” He said it more diplomatically, but he said, “You don’t need to show us that. You just need to listen.” Of course! I took that note and frankly, it was right in a billion ways.

On whether they’d like to work together more:

He: We can dreamweave something. We could approach someone, a smaller theater, and say, “We’d love to do this.”

She: We could pretend to do that, but actors don’t have that kind of power. I don’t know where that world is. It’s not, I wouldn’t think, in the Twin Cities. If there are parts for people our age [she’s 61] and they consider one of us, they certainly have thought of the other one, just because it has happened a lot. It might not be to our advantage that we’ve worked together so much.

He: It is easier to connect again, though. Here, we have the fear thing in common whenever we have to sing. And we’re of an age where, if we’re in a play where there are a lot of young people, we can gravitate to each other.

She: I adore the theater because it’s so generationally mixed up. I get to hang out with the youthquake, but there’s also the comfort in making a reference and having somebody who understands it.