Neville Spencer is a white man who is a member of the Shadowshapers group and has the power to communicate with the spirits of the ancestors through art.
Ol' Vernon has been possessed by a malevolent spirit, and Sierra recognizes him from a mural that she saw at the community center.
Grandpa Lázaro keeps repeating "It's not over," and Sierra thinks that he may be trying to warn them about the danger that the malevolent spirit poses.
Vernon Chandler's photo in the picture hanging on the wall has been defaced and vandalized, possibly by the malevolent spirit.
Sierra gets the clue that the malevolent spirit is connected to Ol' Vernon and the mural at the community center from Abuelo, who tells her that the spirit is looking for a way to enter the physical world.
Vincent is a member of the Shadowshapers group who has been possessed by the malevolent spirit.
Vincent's mural has changed to depict dark and threatening images, possibly as a result of the malevolent spirit's influence.