Lovers of the Four Seasons restaurant in the Seagram building in New York, a masterpiece of high modernist interior design, thought it was bad when, in September 2014, Aby Rosen, the building’s owner, forced the removal of "Le Tricorne", the monumental stage backdrop by Pablo Picasso that had hung in the restaurant for more than 50 years. Rosen trumped up the claim that the wall behind it needed repair but it seems he simply did not want to look at the old painting—which he once charmingly called a schmatte—from the Seagram lobby, which he has festooned with sculpture from his own collection of flashy contemporary art.

But now the threat to the space is far more grave. With their lease ending in July—and the rent rising astronomically—the owners of the Four Seasons felt forced to move to a new location. But now they have announced that on July 26 the auction house Wright will hold an on-site sale of all of the furnishings in the restaurant. This will be no ordinary yard sale, as it will include furniture by Mies Van der Rohe, Eero Saarinen, Hans Wegner and Florence Knoll, and service carts and tableware designed by Garth and Ada Louise Huxtable—all custom-made and in situ since the day the restaurant opened in July of 1959. The Four Seasons is a New York City Interior Landmark, but landmark designation does not protect anything that's not fixed in place. Removal of the Picasso was a loss, but it is safely parked at the New York Historical Society and could easily be returned to the space. Once the furniture is dispersed it will be gone forever.

How did design fans arrive at this sorry pass? The story is hard to pin down. Phyllis Lambert, who was instrumental in the creation of the Seagram Building and the Four Seasons, is the de facto guardian of the architectural legacy of both the office tower designed by Mies van der Rohe and the restaurant designed by Philip Johnson. She says that her nephew, Edgar Bronfman Jr., the principal owner of the Four Seasons, along with Alex von Bidder and Julian Niccolini who operate it, had offered to sell the furnishings to Aby Rosen at less than replacement cost. But Rosen countered with a risibly low offer and then declared he wasn't interested in keeping the old furniture. Officials at RFR Holdings, Rosen's real estate investment company, steadfastly maintain that they tried to purchase the furniture but that the restaurant owners refused to sell. The truth must reside somewhere in between.

Since 2009, I have served as house architect for the Four Seasons, executing a number of renovations until uncertainty over the restaurant's continued tenancy suspended our work. Rosen hired Annabelle Selldorf to complete the restorations. Annabelle and I colluded to encourage our respective clients to do the right thing and keep the restaurant intact, furniture and all. Perhaps naively, we expected rational men to reach an accord that would preserve a cultural landmark, but I fear that the many months of bitter lease negotiations that ended with the Four Seasons' expulsion from the Seagram Building poisoned relations between landlord and tenant such that good faith bargaining was impossible.

Selldorf has now left the project, and William Georgis is now in charge of the design of the new restaurant that will occupy the premises. After Phyllis Lambert published her open letter to Rosen urging him to keep the furnishings in place, Rosen told her that they are working with Knoll to replicate the furniture. In a way, this makes the story even worse: discard the originals and replace them with shiny new copies, tossing authenticity out the window. This is gratuitous destruction, much like the proposal for alterations to the rooms that Selldorf (under duress from her client, I'm sure) presented to the Landmarks Preservation Commission in May 2015, and which the LPC summarily denied. Rosen's behavior is like that of an alpha dog marking his territory and declaring that "this place is mine now, and I'll do with it what I want."

Von Bidder and Niccolini have announced that they will be opening a new Four Seasons a few blocks to the south, on Park Avenue. They have been interviewing international star architects (no, I am not on the list) to create a temple to culinary art for the 21st century, as Philip Johnson's Four Seasons was to the 20th. I wish them luck, but I have my doubts. The Four Seasons is a restaurant at which the venue—the sublime space—has always been a bigger draw than the food. It is a unique example of an extraordinary modernist interior intact down to the chairs and flatware. If it does not remain so, the loss is incalculable.