Continuity mistake: In the beginning of the movie during the skateboard scene with Shaggy and Scooby riding along the conveyor belt, Scooby grabs a hook and both Shaggy and Scooby jump off of the skateboard. You see the skateboard falling off the conveyor belt, but in the next scene it is on the conveyor belt and being crushed. (00:03:20)
Continuity mistake: When Shaggy and Scooby are in the Mystery Machine, cooking and eating food, someone knocks on the door of the van and Shaggy tells Scooby to "Grab the food." Scooby grabs loads of food, and we see two cans of Sprite which are stacked on top of each other, fall to the floor. These then appear back on the shelf on top of each other in the next wideshot, and fall once again! (00:08:10)Hamster
Continuity mistake: When the voodoo man is about to sacrifice his chicken and then Daphne walks in, the voodoo man is clearly barefoot. Then during the conversation between Daphne and him, when we see him fully again, he has sandals on. Then when Daphne leaves his hut he is barefoot once again. (00:20:40 - 00:22:00)Hamster
Continuity mistake: When Shaggy and Scooby are doing the farting competition, Daphne comes and runs a good distance in front of the white/green wall on her left. After cutting to Scooby, we see Daphne walking out from the dark and passes the wall that she is supposed to have already passed. (00:33:20)
Continuity mistake: When the monster comes out of Daphne's body, Velma runs to the window and her right hand is about to open the blind (she holds the string). When the shot cuts to Daphne, we can see the lower part of Velma's body in the background with both of her hands down (doing nothing). When the shot cuts to Velma again, her right hand is up and about to pull the string. (00:53:35)
Continuity mistake: When we see the very first close shot of Emile Mondavarious' desk, the black lampshade on the desk is very close to the books that stand on his desk. Yet when we see the desk in the background, when Emile is talking to Scooby, the lamp has moved much farther away, and in the space that it has moved away, a figurine has appeared too. (00:57:45)Hamster
Continuity mistake: When Daphne is fighting on the roof with the wrestler, you can see the lever in the background which Daphne is supposed to pull. Above the lever is a sign which says "CAUTION - Clear vents before opening." Throughout the fighting scene the branches/vines that are beside the sign constantly go from hanging over the sign, to beside the sign. (01:09:00)Hamster
Continuity mistake: When Scooby-Doo falls down the hole to the cavern below Shaggy follows him a few seconds later. When Shaggy hits the sand below he has to roll when he hits the ground. In doing so, his back and knees are covered in what appear to be thick sand deposits. When he stands up in the next shot and turns around he has no sand on his knees or on his back. He has not made an effort to brush his pants or shirt off.