The boy's school telephones his home to say that he hasn't shown up. But when the kidnapper calls he says that he has told the school that the child was ill and so would not be coming, so that no one would worry when he did not turn up.
When Parnell first enters the estate agents' office, the clock on the wall indicates a time of roughly 9:35. A few seconds later, the clock reads 9:43.
The police were told that the bomb planted in the house was large enough to blow the side if the house out yet when the boy's taken downstairs there's about a half a dozen reporters and photographers plus the boy's father in the hallway. The police wouldn't have allowed them anywhere near.
In a shot of the drive way as the assistant commissioners car drives up the rear of Gregson's car can be seen yet when the boy and his father leave the house his is now facing the opposite direction and all the police cars have disappeared.
When Parnell and Grey first meet the local police officer near Chester's house, a cylindrical microphone windshield is very obvious at the bottom of the frame.
At the house where the boy is being held the press and the boy's father arrive straight after the police yet they hadn't been notified of the location of the house.