10 Best Last Minute Replacements For Actors In Major Movies

3. Paul Dano Over Kel O'Neill (There Will Be Blood)

Paul Thomas Anderson's towering 2008 masterpiece is a perfect convergence of so many incredible elements, not least the fantastic two-hander between Daniel Day-Lewis and co-star Paul Dano.

However, this wasn't always the plan, and though Dano ultimately played the dual role of brothers Eli and Paul Sunday, he was originally only cast as Paul, with largely unknown actor Kel O'Neill playing Eli. Several weeks into shooting, though, O'Neill was fired from the film by Anderson for reasons that remain up in the air.

Reports at the time suggested that the young actor was intimidated by Day-Lewis' intense performance style, though O'Neill himself claimed last year that it was simply an issue of chemistry, and he wasn't giving Anderson the performance he desired.

Ultimately, Dano gave a brilliant, awards-worthy performance in his own right, while O'Neill has gone on to have a successful career as an independent filmmaker. When a director of Anderson's calibre thinks that a performance isn't working, he's almost definitely right, so there's no arguing with this one.