Errores

When the kids are in the tunnels and using their torches, the circle of light from the torches don't match where they are actually pointing them.

When the Rhona Davis' character is being tied up, a part of the rope goes around her neck. Next shot the rope is lower. Also, the amount of rope around her changes after the children discover the letter to her other name, Rhona Watson.

When Joe Kirby first looks at the milk-bar shop front (near the beginning, just after asking the man with the open top car if he is Selwyn Pike), the light fitting casts a very long shadow. But in the next shot of the shop, it is lit from a different direction, and the shadow has completely changed in length and position.

When the children leave the sewer via the man hole cover, none of the boys' trousers are wet. When the children are seen running down the street away from the camera, the girl is leading the group but she was not shown emerging from the manhole. The clip is very short but in slow motion the girl's dress and legs can be seen, and therefore the lead person must be the girl.

When the Rhona is being interrogated, the mouse is on her right leg in close up and her left leg at a distance.