After about 1 hour 10 minutes into the movie, (after they all tell the story about Scrappy Doo), everyone is in the lobby. Scooby Doo gets scared because someone said "ghost" and hides underneath a stone-like table. Fred gets a little impatient with Scooby Doo and tells him that there are "no such things as ghosts". While he talks to Scooby Doo, the camera changes views, and Scooby who is supposed to be under the table now disappeared! Fred is talking to an empty space. Fred then walks on top of the table and Scooby still not there. I guess someone forgot to draw Scooby Doo for that second angle!