Never review a film you haven't seen
...It could be Citizen Kane.
Mark Kermode's refrain when occasionally - usually through spending compulsory family fun time on the Wittertainment Cruise - he has not seen a film in the UK Top 10 but is asked his opinion on it anyway.
Apparently, some other critics are known to have reviewed films they haven't seen anyway. In Hatchet Job, Mark points out that James Silver of The Guardian highlighted Johnny Vaughan was very rarely present at screenings, despite the large number of reviews in his name in The Sun. Vaughan's spokesman replied that he was "lucky enough to have super-special private screenings." Meanwhile Mark also gave the example of 5 Live's own Richard Bacon cheerfully admitting in his 2013 memoir A Series Of Unrelated Events that he neither watched the films nor wrote the copy for his reviews in The People newspaper, eventually being caught out when he told the publicist of The Lake House that he would definitely try to see the film, only for her to reply that he had not only reviewed it, he had hated it.
The Wind That Shakes The Barley was condemned by a number of British critics who had not seen the film. Similarly, Angels and Demons was condemned by one leading Catholic critic who had not seen it, prompting one reader response that said "You are a man of great faith: you believe, although you have not seen." Mark thought this was a funnier joke than anything in the film.