At the beginning of the movie, Wade greets Mrs. Gilmore as he comes down the stack that both of them live in. Mrs. Gilmore gives Wade a friendly greeting in return.
Despite living in the same stack as Wade, Mrs. Gilmore survives IOI's bombing of it. Along with everyone else, she watches Parzival complete the final challenge to get the Crystal Key and learns that Parzival is Wade when he calls for help from everyone in the Columbus Stacks. When Nolan Sorrento arrives after wrecking Helen Harris' postal van in the Stacks, Mrs. Gilmore is the first to confront him, angrily telling Sorrento that they know what he did there. She and the other residents of the Stacks are forced to back off when Sorrento pulls out a gun, but slow him down enough for Wade to win the Golden Egg and control of the OASIS.
In the aftermath of Wade winning the Golden Egg and Sorrento's arrest, Mrs. Gilmore and the other residents of the Stacks celebrate the High Five's win.