Worst casting in a film

[Sky Blue]

Ray Winstone whenever he has to play someone with a different accent to a cockney.

His American accent in the Departed was hilariously bad.

Beat me to it. Absolutely shocking.

Dick Van Dyke playing the chimney sweep in Mary Poppins was probably the worst ever attempt at a cockney accent.

 

[dickie davies]

Robert Carlyle in "The 51st State"

In fact any film where he's not supposed to have a Scottish accent.
Same for Sean Connery. The hunt for Red October and Highlander immediately spring to mind

 

[Double R]

Whilst he has made a head of dross, I'd recommend watching "Mandy". Is the exception to the rule. And a great performance by Nic.

Red Rock West, was a cracking film too.

 

[Double R]

Keanu Reeves in 'Barm' Stokers Dracula.
Sean Connery's irishman in Untouchables.
Mathew Goode as Ozymandis in Watchmen.
QT in everything. Terrible actor.
Vince Vaughn. Psycho remake.

 

[Zin 'messiah' Zimmer]

Don Cheadle in Oceans Eleven. The British accent has to be one of the worst ever recorded on film.

 

[Zin 'messiah' Zimmer]

The doll in Pinocchio, wooden as fuck!

 

[Bob Hope]

The doll in Pinocchio, wooden as fuck!

That's just not true.

 

[Zin 'messiah' Zimmer]

That's just not true.

could of been written by your namesake himself (if he’d written any of his material (: )

 

[jimharri]

Beat me to it. Absolutely shocking.

Dick Van Dyke playing the chimney sweep in Mary Poppins was probably the worst ever attempt at a cockney accent.

Natalie Portman's "English" accent in V for Vendetta is, er, uniques.

 

[Patientman63]

Jack Black in anything remotely romantic, such as The Holiday....

Shallow Hal on the other hand...