If all the world's a stage, why can't shows from Broadway, London, and even Philadelphia be playing on it, simultaneously?

That's the billion-dollar question the fairly new online video service BroadwayHD is testing Thursday night, as it offers up the first-ever live stream of a Broadway show, the musical revival She Loves Me. And in the process, the start-up hopes to cement its status as the "Netflix of Broadway."

Well-reviewed and nearing the end of its run at Studio 54, this internet treat features a top-notch score by Sheldon Harnick and Jerry Bock (of Fiddler on the Roof fame) and a well-known cast (a high priority for BroadwayHD masterminds Stewart Lane and Bonnie Comley), including Laura Benanti of Nashville.

She Loves Me - which will be available for a week at BroadwayHD.com - tells the story of rival perfume shop employees unaware that they're each other's romantic pen pal. The same play also inspired the Tom Hanks- Meg Ryan film smash You've Got Mail.

While tickets to the New York production are going for $52 to $147, the streamed show - offering 10 camera angles - goes for a mere $9.99 on computers, tablets, and smartphones. Or you can enjoy it on big TV screens by using Apple TV and Roku set-top boxes, but only if you pick a $169.99 (year-long) or $14.99 (one month) subscription to BroadwayHD.

This service was launched in October with more than 100 viewing options "from Shakespeare to Sondheim." There's a lot of BBC-TV and West End London stage content, some concerts, and a few recent off-Broadway things (Buried Child, Old Hats). You won't find many shows shot in a Broadway theater.

Why?

Stage unions resisted the intrusion. For decades, producers could make only archival films with a single, balcony-mounted camera. (Lots are at the New York Public Library for the Performing Arts at Lincoln Center.)

But the walls have been coming down.

Even at the regional theater level, "you need production clips to post on social media to promote your show," said Abigail Adams, CEO of the People's Light and Theatre Company in Malvern.

There's also growing evidence that full-length videos help rekindle interest in live stage versions. A video of the stage musical Memphis played at movie theaters without harming road show grosses, said BroadwayHD's Lane.

Ratings for the December NBC production of The Wiz Live! were so strong that a new Broadway version is now being plotted, said Philadelphia-based show producer Larry Magid. And while recent free streamings of the off-Broadway musical Daddy Long Legs - viewed by 150,000 people worldwide - failed to achieve a fast transfer to Broadway, "it looks like they're getting an L.A. production," he noted.

An offer from HBO to capture Billy Crystal's 500 Sundays on stage in New York "got the show back on Broadway," said Magid, lead producer for Crystal's comic memoir and a force behind the Carole King musical Beautiful.

500 Sundays is a one-man, single-set show, but the video costs "were still high," Magid said. "So imagine what it must be with a musical like She Loves Me," with a 25-member cast, an orchestra, and many union stage hands, all earning extra pay. The authors have to get paid, too, along with the originating theater.

Still, with Broadway grosses at record levels - Hamilton earning $1 million profit a week - the sentiment is growing that a site such as BroadwayHD is worthwhile even if She Loves Me doesn't recoup its video costs.

Comley has been encouraged by sign-ups at broadwayhd.com. Folks in the Tri-State area who can drive in were pleased, she said. But "people who were outside of the area were throwing roses at our feet."

Also, the audience is "skewing a lot younger than the typical live theater demographic" (of well-educated, affluent women over 45) "and we're getting males."

Is there a place online for regional theaters to do this, too? People's Light's Adams would argue not - that "costs are prohibitive and our focus . . . is to get people into the seats."

How about to spread the word to the good folks in Boise about that potent new play, The Harassment of Iris Malloy, loosely inspired by Bill Clinton and Paula Jones, that is premiering in Malvern now? "I'd rather Boise's resident theater company put on its own production!" said Adams.

215-854-5960 @JTakiff