Plot hole: The whole problem with the teleporter occurs when fly DNA is mixed in with Seth Brundle's DNA, starting his transformation into the Brundlefly. Brundle is on a hiding to nothing from the word go, and the fly is irrelevant. Humans are a walking talking mass of foreign DNA - we are host to one trillion bacteria all of which has a complete compliment of DNA, as do various tiny mites that live in our hair follicles and all sorts of single cell organisms in our gut. If the transporter serves to mix the DNA of all living creatures which are in the transporter pod at the time Brundle would turn into a half-man, half-bacteria. Incidentally, DNA from a bacteria, an amoeba or a hair follicle mite would be just as 'compatible' with human DNA as that from an insect. It's quite a simple chemical, really.
Continuity mistake: When Baby Secret Bear and Baby Tenderheart jump on the rainbow to leave the cloud boat, you can see their "tummy symbols", which they have not yet received. The symbols disappear as they are sliding, then when they reach the bottom of the rainbow, the symbols are given to them for the first time. (00:06:35)Kathy Tjarks
Continuity mistake: When Jack Burton and the rest of the gang escape from the Wing Kong Trade Centre the first time, the guards fire at the left side of the bus breaking the windows and making holes in the bodywork. When we see the bus a few seconds later as it is driving away, it appears undamaged.tw_stuart
Continuity mistake: In the opening scene the camera pulls back from a bedside locker to an over the shoulder shot of Kathleen Turner's character doing her make up in the mirror. Close inspection shows that the shoulder in the foreground is actually that of a double who doesn't quite match Turner's movements.
Other mistake: In the first scene when the hurricane has passed and Pazu and Sheeta land on the cloud, Pazu twirls Sheeta around until they are almost off the edge of the cloud (his toe actually is on the edge of the cloud). But in the next few seconds the direction changes and they end up back on the cloud.
Continuity mistake: Torok the Troll wears a magic silver ring which allows him to appear in the form of Wendy Potter. However after Wendy's mother tells her about the orange juice, when Wendy touches the cold bottle of milk in the fridge she grabs her arm in pain and we can see both of her hands, and she's not wearing that magic ring.Super Grover