DUMBO hotspot reBar abruptly shut down Friday — leaving 53 stunned employees out of a job and panicked couples who had booked weddings there scrambling to come up with a Plan B.

“ReBar is closed and bankrupt. DO NOT ENTER,” read a sign greeting workers reporting for duty at the 147 Front St. gastropub.

Aisling Jumper and her fiance Scott Mathews-Novelli, both 32, had already plunked down $14,000 for their wedding at reBar — set for August 9.

“My family is literally flying in from all over the world,” a tearful Jumper told The Post. “Our date is not movable. We’re getting married that weekend.”

The Irish native’s mom still lives across the pond and she has friends and family flying in from New Zealand and England as well.

They couple had met with reBar staffers only Thursday to iron out some final details — and were given no hint that the place was about to go belly up.

Later Friday, she was grateful to reBar’s staff for doing their best to help them out.

“The staff are being amazing. They don’t know what happened but are doing everything they can to make it right,” she said in an email.

Another couple whose wedding was set for Saturday is moving the bash across the street to Baco DUMBO, where the staff jumped in to bail them out, reBar staffers said.

But there are about 200 other weddings booked from Sunday to several months out, staffers said.

“We’re trying to do it just one wedding at a time,” distraught manager Dina Thaverne, 36, said. “Everyone got hit at the same time.”

ReBar owner Jason Stevens sent an email at 6:19 a.m. to the gastropub’s managers early Friday, informing them to get rid of their keys and asking them to forward the bad news to any staff not

included on his email.

He apparently took off with whatever money the business had and no one has been able to get in touch with him, Thaverne said.

“He took the money and ran,” she said. “If you think about it, there are people that are calling in who had weddings ranging from $6,000 to $35,000. They’re expecting to have a wedding here. It looks like that’s not going to happen.”

Another manager, Orlando St. Preux, who worked there for seven years, was floored by the news.

“Business has been great, we have weddings every weekend. We didn’t see any of this coming. We took deposits and everything from people yesterday. If I saw a bride and groom yesterday and I knew it was coming, I would’ve told them don’t give your money,” he said.

To make matters worse for the workers, Friday was payday.

After getting the bad news, staff gathered across the street at Superfine, a neighboring restaurant, to try to figure out what their next moves would be.

“They were in shock and disbelief,” said Cara Lee Sparry, co-owner of Superfine. “They were bewildered.

Other local businesses, including Brooklyn Winery, Superfine, and Fornino, have all offered to help couples left high and dry by reBar and are even offering them a break on their bills.

Jumper, meanwhile, sympathized with the staffers, saying, “It sucks for them.” she said. “It’s not a fly-by-night place. It’s an established business.”

A lawyer, Jumper said she and her fiance already kissed her $14,000 goodbye for now, but plan to take legal action to try to get the money back.

“We’re starting back at square one,” Jumper said. “We’re supposed to be almost done with it. We have no money. We’re broke.”