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.
Other mistake: The walls of Frank's house wobble whenever he opens the front door.
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.
Continuity mistake: When the mini goes into the horse box, Frank is on the roof. When it stops, Frank is thrown onto the horse's back. But when the car first goes into the horse box, there is no horse inside it. Also, you can see the ramps put on the tailboard so the car can drive up it. They fall away as the horse box drives off.
Continuity mistake: When Frank is taking his driving test in the Hillman Imp, he is driving slowly down a narrow and winding road. He is being followed by the green van, flashing its lights at him, and as the van turns off Frank hears a train hoot, then drives round the barriers at a level crossing. The terrain suddenly changes from a narrow road in the hills, to a wide road on flat land. Then while Frank is driving to the sea, he passes the same parked brown Vauxhall Victor twice.
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.
Continuity mistake: Just before Frank's car crashes into the sea, the shots from inside and outside the car do not match. Outside shots show Frank driving in a built up area while inside shots show countryside.
Continuity mistake: When Frank is driving the white mini in the country lane, trying to overtake the lady on the bike, there is nothing behind the mini, but then a split second later he is being followed by a silver Renault. As he tries to overtake the cyclist, Frank is followed by a brown Triumph, then a second later a yellow Ford Anglia is following him. Frank also appears to drive along the same stretch of road several times, as he keeps passing the same parked cars.
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.
Visible crew/equipment: In the first scene, the shadow of the mic can be seen on Mr. Wheeler's Santa Claus outfit.
Visible crew/equipment: Crew members can be seen in the background and behind the trees when Frank is on the roof of the runaway mini when it is on the pavement and knocks the walking stick out of the man's hand.
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.
Continuity mistake: Mr. Finney is explaining the mirror signal manouver procedure to Frank during his driving lesson in the white Mini. While they are parked, the shots from inside the car show a line of parked cars behind the white Mini. But when Frank moves off, the shots from outside the car show no cars parked behind the Mini.
Continuity mistake: Several times when Frank is having his driving lesson in the white Mini, the shots from inside the car don't match the shots from outside the car.
