Michael Hollinger is juggling two plays in Philly at once. Again.

"I'm feeling a little like a bigamist who is moving between these two families," says playwright Michael Hollinger. "The good thing is they know about each other and neither begrudges my being at the other's place."

What's this? True confessions of a dramatist? Not exactly. For the second straight season, not one but two of Hollinger's plays are on at the same time: Sing the Body Electric, a world premiere at Theatre Exile (through May 13); and Hope and Gravity at 1812 Productions (April 26-May 20).

So he's had to be around, for both companies, answering questions, making occasional comments or suggestions, being a collaborator … in two places at once.

It was easier early this month, because Exile and 1812 were rehearsing just a floor apart at 1812's offices on South Third Street. Hollinger was going up and down stairs, from one company, one dramatic world, to another, trying to give equal time. He let us tag along for those early sessions.

It was intense. As the directors and actors tried out various ways of doing lines and scenes, Hollinger was as focused as you can be.

In an early rehearsal for Hope and Gravity, the 1812 cast came to a scene in which an older couple is selling their longtime family home to a younger couple. The sellers have many powerful feelings, including sorrow and regret; the buyers, while trying to be polite, are trained mostly on their present and future. The cross-generation talk is bumpy, awkward. The two men try to shoot the breeze about the house.

Hollinger: "It should be like guys talking about lawns." Laughter.

Director Jennifer Childs, Hollinger, and the cast discussed the characters' emotional states, real estate issues, house prices. One actor read a line, and Childs said to its recipient: "What do you think you're going to say when you hear someone say that to you?"

Suli Holum as Nan, the older woman, said, "Let's talk about why we're motivated sellers," and Sean Close as Steve, the younger man, thought out loud, "So this is a year after we've graduated? And then we got married? And I'm having some success now as an ad writer, and it's all going too fast? And my wife can think quicker, and I'm more passive?"

Hollinger nodded.

Jessica Johnson as Jen said, "Right, if I'm seven to eight months pregnant, I'm thinking, 'We've got to move on this.' "

Hollinger agreed: "There's a number of times when you say, 'I think we've seen all we have to see,' and that's for your husband's benefit."

At Theatre Exile, the feeling was different, maybe because this is a brand-new play (Hope and Gravity was first produced in 2014) and everyone was feeling their way forward together. Scenes alternate: In one, Lloyd (played by Anthony Lawton) angrily interrogates Doris (Kimberly S. Fairbanks), and in another, Blake (Trevor William Fayle), a young man who has survived a lightning strike, tries to duck questions from a fascinated Jess (Kishia Nixon).

It was remarkable how much Hollinger did not say. As with director Childs and Hope and Gravity, here the reins were firmly in director Deborah Block's hands. (Later, Hollinger said, "One of the keys to this thing is that Jen, Deborah, and I have known each other for a long time, and there's a lot of trust there.")

On this day, the comments and focus centered on movement. Doris tried different ways of walking uncomfortably around a table as Lloyd grilled her with rising anger. At one point in the play, Jess gets Blake to take his shirt off, and she sees his scars from the lightning strike. Blake says, in a small voice, that the scars are called "Lichtenberg figures," which make patterns like fractals.

Block said, "That was great. The voice you used there, just great."

They did the scene again, and at one point, while Blake struggled to explain, Jess walked across the imaginary "stage." She hadn't done that before. Block said, with a smile: "I liked when you walked across like that. That sort of changed the whole scene." Hollinger was also smiling. They might keep that one.

Those were the early days. Soon, the companies departed to their separate theaters. Theatre Exile went to its temporary digs at the Latvian Society on North Seventh Street (its longtime home is being renovated), and 1812 went to its home at Plays and Players Theatre on Delancey Place. So Hollinger started making a crosstown trek, and he let our photographer go along.

Clearly, Hollinger can't really escape being a kind of authority, to be consulted for advice, clarification, opinion – but he is also careful, picking moments, letting the pros do their jobs. And that, he said later, is tough.

"Everything I'm watching, I'm asking, 'Is it true?' " he said. "As the actors try things different ways, is it still true? Is this way truer than that?"

He's particularly alert, he said, for "where the lies show up," where something doesn't seem true to life. "The lie might be in the writing, in which case I need to rewrite. The lie might be in the staging, where you might say, 'Well, the line is fine, but the person wouldn't say that standing, or standing this particular way with this other person.' Or the lie might be in the acting. Then you might say, 'Yeah, but they wouldn't laugh when they say that' or, 'They would laugh when they say that, not keep a straight face.' "

The trick is knowing when to speak up and when not. "My first and hardest tack," he said, "is to just wait, because if your collaborators are smart and observant – and, thank goodness, my collaborators here are – they will also find solutions. It's always better if the director and the actors find it themselves."

Last fall, the two Hollinger plays were Red Herring, a 2000 comedy that had a sparkling run at Act II Playhouse in Ambler, and TouchTones, a world-premiere musical at the Arden Theatre Company. Hollinger called TouchTones "a mammoth project that was brand-new and therefore prone to big rewrites at the last moment."

"There's so much doubt with a musical," he said. "You keep thinking, 'What if it's no good? What if I've wasted 12 years of my life working on this?' And it was much harder making changes, especially when songs or music were involved. Each change means making 10 other changes."

Red Herring is a tight, well-honed, indestructible romp, "and with that, I could just sit back and let the actors work. It's a comfort," he said, looking at his watch and wondering where to be next, "just to let go and let the process be the process."