The pop-up began when a large glass box appeared in Grand Central's Vanderbilt Hall, containing a replica of the four-seated desk from Lumon's Macrodata Refinement department. Hired actors playing Lumon employees sat at their desks, doing Lumon things (by which I mean, sorting numbers while not having a clue what said numbers mean).

According to the New York Post, for around two and a half hours, starting at 4:30 PM, they remained in character, much to the amusement of the commuters. It was an unusual and captivating promotional stunt, bringing the world of Severance directly to New York ‘s busiest transit hub.