It has widely been assumed that Dick Van Dykes accent in Mary Poppins was the worst movie accent of all time,
Van Dyke's début at about 3:30
Now, whilst it is really, really bad I have recently discovered “The Lady from Shanghai”, a film in which Orson Welles attempts an Irish accent. Here are the first few minutes of that film. Orson does a voice over after about 1 minute in and that really is his Irish accent. Worse even then Pierce Brosnan's but he is Irish so what was his excuse?
Orson Welles' penultimate movie role anyone? Come on, you can get this one....
No? Anyone? Is this on? Fine, Transformers The Movie.
He played Unicron.
I would then like to draw you attention to Johnny Deep in From Hell, it's a terrible, terrible attempt at the English accent,
But is it the worst?
Also for you consideration there is the ever wooden Keanu Reeves in Bram Stoker's Dracula,
That English as well I'm told.
Don't worry, I'm not here to just take the piss out of American actors attempting an English accent, plenty of other actors have tried, and failed, accents that are not there own.
Ewan McGregor, for instance, is rarely in a good film but in Angels and Demons he combined his “anything for cash” approach to reading scripts with an accent so bad I defy you to guess where his character is from after watching this trailer,
Northern Irish I'm told.
These are just a selection of the worst accents. Please make you own suggestions. It's fun.