Factual error: In the scene where Arthur first enters the house and starts going through paperwork, there's a shot of Nathaniel Drablow's death certificate which shows 'body was not recovered' in the box next to his cause of death. Such a thing would not be written on death certificates of the time - that box is reserved for 'Signature, description and residence of informant', a heading which can partially be seen as the camera pans across the certificate. For the death to have been registered, an informant's signature would have to have been there. (00:20:05)
Factual error: The driver who first takes Daniel Radcliffe to the haunted house tells him that the tide will be out at 5pm, enabling him to return and collect Radcliffe. A day or two later, Ciaran Hinds says it will happen at 11pm. This is not possible - tide times cannot change by that much in the space of a couple of days.
Factual error: During the film Daniel Radcliffe is not seen wearing, or even carrying, a hat on a single occasion. In Edwardian times a man would not have gone outside without a hat on, particularly a member of the professional class.
