By Friday morning, most of Broadway had heard: Early during the first New York preview of  the much-anticipated London hit “Groundhog Day,” the set’s revolving stage stopped working — and stayed broken for the duration of the show.

But instead of calling the whole thing off, the cast, crew and audience banded together to turn a massive malfunction into one of the more memorable first performances to come along in a while. After about half an hour of trying to fix the turntable — during which producers offered audience members free drinks — the cast went on with the show, in the form of a concert version of the first act followed by highlights from the second act.

“It turned the whole night into something more, because the audience was there for us, to push us on in a way where they felt like they were really a part of it,” said star Andy Karl (“Rocky”), speaking between a rehearsal Friday afternoon and the second preview performance that night. “It’s that thing theater does: ‘Let’s build this barn no matter what!'”

Before the breakdown, it had all been going so well. “We were only about 15 minutes in, and the show was going like gangbusters,” Karl recalled. “I had a little bit of nervous energy, but it felt like the right amount of it. And then all of a sudden, after the first big number and the first big speech that I do, we were about to go to another scene, and the set was supposed to revolve and we were about to see a person dressed in a groundhog outfit. But it just didn’t happen.”

It turns out to be an electrical glitch, but no one figured that out until later. After about 30 minutes of failing to diagnose to the problem, the show’s director, Matthew Warchus (“Matilda”), suggested the concert staging.

Onto the stalled stage, the crew brought out enough furniture from the show’s various sets to seat the entire cast, and the actors and orchestra forged ahead. There were no costume changes, but the lighting designer and the spotlight operators improvised some lighting.

To judge from the reaction on social media, theatergoers in the crowd that night loved being part of the unique event. Producers, meanwhile, offered tickets to come back to see the production again — this time with a working set.

The whole event made for the kind of communal experience at which theater excels. “I could never imagine a more perfect imperfection,” Karl said.

Not that he’s hoping for something like that to happen again. “I’m excited for tonight to work,” he added with a laugh. “We did it this afternoon without a glitch!”