Revealing mistakes: A lighter can be seen in Gadget's hand when the fire is supposed to come from his thumb.
Continuity: In the scenes where Sikes is wearing the electronic helmet, the chin strap is fastened, then loose and then fastened again.
Continuity: When Inspector Gadget falls on top of Brenda in the building, the position of their faces rapidly changes between shots.
Crew or equipment visible: When Gadget is hanging off the building at the end of the movie, a crewman's shadow can be seen for a short time during the overhead view.
Continuity: As John Brown wakes up after being transformed into Inspector Gadget, he falls off the right side of the table. An overhead shot of the operating room shows him on the other side of the table as he is getting back up.
Continuity: After John Brown is made into Gadget he exits the room with wires around him, but before he exits he had no wires.
Continuity: The fender of Claw's limosine is clearly damaged after colliding with the gadgetmobile. However, in the next shot the damage has repaired itself.
Continuity: When Gadget is found in the scrap yard, the machinery in his stomach is visible. When he gets up, he is suddenly wearing a shirt, and the machinery can no longer be seen.
Revealing mistakes: In the scene when Scolex brings RoboGadget to life, in the close up shots of RoboGadget's head, the collar of a grey t-shirt can be seen. But in shots where we see his body, it is all machinery below his neck.