Like a phoenix, Flex Mussels has risen from the ashes of a devastating fire last winter, spending months transforming a shuttered space into a magnificent new flagship that’s sure to draw diners from across the city to the Upper East Side for their elevated seafood fare that flexes on the competition.

Located at 1431 Third Avenue, at the corner of East 81st Street, Flex Mussels takes over the sprawling two-story space formerly home to Mediterranean restaurant Beyoglu, which closed in 2020 after more than twenty years. Flex has transformed the restaurant inside and out, brightened from a dark blue storefront with large awnings to a beachy off-white with light green overhangs.
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A bright new neon sign, featuring with the word ‘FLEX’ bookended with shells, hangs from the corner of the building— a beacon for hungry Upper East Siders searching for their seafood fix.

Step inside and you’ll be dazzled— either by the grandeur of the months-long renovation itself, which was documented by Flex Mussels on social media, or by the array of globe-shaped light fixtures hanging from the extra high ceiling and the LED-lighting under the steps of the staircase leading to the spacious second floor dining area– which will eventually have its own bar and a private dining room.

Rewind the clock six months and it was a much different story.
On the morning last Valentine’s Day, February 14th, a fire broke out in the kitchen of Flex Mussels original restaurant, located at 174 East 82nd Street. The flames sparked around 10:35 am, while the restaurant was still closed.

Firefighters were able to contain the fire to the rear of the building, however, the restaurant suffered significant damage and the Flex Mussels team said it would closed for several weeks for renovations.

Those weeks turned into months and eventually the original Flex location would never reopen as the team focused their efforts on the new Third Avenue space, which they had already been working on since 2021.

Tuesday marked the second night of two ‘friends and family’ preview events at the restaurant and included a sampling of the popular seafood purveyor’s new menu— which has been elevated along with everything else about the dining experience.
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Don’t worry though, mainstays like the homemade donuts aren’t going anywhere.

Flex Mussels will begin welcoming diners this Thursday, August 25th, marking the start of the restaurant’s soft opening.
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