Revealing mistake: Harold is taking his family for a drive in his brand-new Butterfly Eight automobile. He drives as fast as 50 miles an hour. Three times, a close-up of the speedometer and odometer is shown but the mileage never changes. It stays at 2.4 miles.
Revealing mistake: When Harold jumps onto the rear of the fire truck, the cable attached to him at his chest can be seen during the stunt. (01:06:25)