Revealing mistake: When Arthur goes into the marsh to bring Nathaniel's corpse up, each time he emerges to get air, you can see the lack of mud around his lips from an air mask.
Revealing mistake: When Mr Kipps comes back in into the house after seeing the ghosts of the children in the front garden, he looks down and sees footprints. The error is the footprints are far too uniform and equally spaced at regular intervals to look natural. It looks as though a template has been used to print them on the floor. (00:59:45 - 01:00:20)
