Revealing mistake: When Frank is the pixie in Santa's grotto, a young boy fires something at Frank from his catapult. Although Frank reacts as being hit, the boy doesn't actually fire anything at all.
Revealing mistake: When the bottle of wine explodes in the cupboard, just after Frank has shaken it, you can see a pushrod inside the cupoboard pushing the top up.
Revealing mistake: Just before the runaway mini goes into the horsebox you can see the stunt man dressed all in black laying down inside the car steering it.
Revealing mistake: While Frank is taking his driving test, he and Mr. Hayes are wearing standard road safety belts in the car. But when the car is in the sea after crashing through the fence, both the occupants are wearing motor racing type safety harness obviously fitted for the stunt.
Revealing mistake: When Frank drives his car into the sea, he and Mr. Hayes escape through the sunroof. You can see that the actor playing Mr. Hayes has been changed to a stuntman as the hairstyle has changed and he is wearing a lighter coloured suit.
Revealing mistake: When the flying saucer crashes down onto the wishing well, it is obvious that the Father Christmas in the saucer is a dummy.
