Actors Michael Glenn and Dawn Ursula share an awkward smooch in 'Stage Kiss' at Round House Theatre. (Cheyenne Michaels) Actors Michael Glenn and Dawn Ursula share an awkward smooch in ‘Stage Kiss’ at Round House Theatre. (Cheyenne Michaels)

If any of the actors in “Stage Kiss” catches a cold, the whole cast is going down.

“There is a shocking amount of kissing in this show — almost every character ends up kissing someone — so I’m knocking on wood and telling everyone to take their echinacea and vitamin C,” says Aaron Posner, director of the comedy’s regional premiere at Round House Theatre, where the show runs through Dec. 27.

The actress most in need of an immunity boost is Dawn Ursula, who lands 29 kisses while portraying an actress who gets cast opposite her former boyfriend in a terrible, 1930s-set melodrama called “The Last Kiss.”

“The play-within-the-play aspect is just so juicy,” Ursula says, “especially when something is happening between my character and her ex, and they are able to have this conversation through the lines they are rehearsing together.”

Ursula’s character (known only as “She”) gets out some aggression toward her former flame (known as “He”) by choreographing a slap into a smooching scene. The onstage violence is faked, but the kisses are real, Ursula says.

“Actors used to do stage kisses with their lips pressed tightly together, but audiences today would find that unrealistic,” she says.

That means there’s not much difference between a modern stage kiss and a real one, which is why She and He end up rekindling their old romance. There’s even a term for when fictional romances cross into the real world.

“Showmance happens all the time,” Posner says. “Two people are asked to invest their heart and spirit and soul in pretending to be in love, and they end up in an affair. It’s what happened with Angelina and Brad, Bogart and Bacall.”

But this play isn’t only about two actors in love. It’s also about the thin line between fantasy and reality — especially when it comes to relationships.

“In any true relationship, there’s some degree of pretending. You don’t always feel everything you’re saying, even if you wish you did,” Posner says.

One particularly clever way “Stage Kiss” messes with the distinction between reality and fiction is through music. At the beginning of the play, music is supplied by an actor playing the part of a rehearsal pianist. Later, when the ex-lovers share a private moment, the still-onstage pianist lands a perfectly placed arpeggio, and the two look at him in surprise. Toward the end of the play, the pianist provides offstage musical accompaniment during scenes his character would have no reason to be near.

If this all sounds confusing, it’s not, Posner assures.“I think it’s actually pretty easy to follow, even though it’s got all these levels of meta-theatrics,” he says. “At its soul, ‘Stage Kiss’ is a comic romp about love and romance.”

Round House Theatre, 4545 East-West Highway, Bethesda; through Dec. 27, $30-$66.

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