The ghost of Allison Argent played a big role in the Teen Wolf Season 5 Finale “Apotheosis“. Scott’s memories of his first love ultimately saved the day when Sebastien, The Beast of Gevaudan, tapped into his brain and saw what he thought was his sister Marie-Jeanne Valet.
However, there are some fans who believe Allison’s spirit made another appearance in the show.
In that penultimate scene there was a fourth chair. Many fans believe it was left for Allison but some saw something else in that scene. They claim Allison’s chair moved as if someone pulled it out, sat down and then pulled closer to the table.
Tumblr iamthealphanoww provided evidence in a series of images.
“The chair went from in, to out, to back in. So are we just going to pretend like we didn’t witness Allison’s ghost joining the group.” – iamthealphanoww
The movement of the chair could be a purposeful choice by the director or it could just be a continuity error caused by accident while shooting the various scenes that make up that segment.
While both of those “real world” explanations make sense, the Ghost Chair theory is more fun.