Helen Mirren as Queen Elizabeth II in 'The Queen'
Mirren is no stranger to royalty. She has played a queen in the drama The Madness Of King George, '80s comedy The Fiendish Plot Of Dr. Fu Manchu and portrayed Elizabeth I in a TV miniseries of the same name. But her most famous queen was, of course, Elizabeth II who she played in The Queen. It won her an Oscar for Best Actress and she reprised the role on stage for The Audience.
Charlize Theron as Aileen Wuornos in 'Monster'
The Mad Max: Fury Road star gained 30 pounds, wore prosthetic teeth and went through a dramatic physical transformation to play Aileen Wournos, the real life serial killer who is the subject of the film Monster. She won an Oscar for her role, in which she is barely recognisable, and film critic Roger Ebert called it "one of the best performances in the history of cinema".
Robert Downey Jr. as Charlie Chaplin in 'Chaplin'
TriStar fought for many different actors to play the role of fames silent film star Charlie Chaplin in Richard Attenborough's film. Jim Carrey, Robin Williams and Billy Crystal were all approached. But Attenborough remained vigilant; he wanted Downey Jr. The actor went on to win a BAFTA and be nominated for an Oscar and Golden Globe for the performance.
Eddie Redmayne as Stephen Hawking in 'The Theory Of Everything'
Eddie Redmayne represented Britain at the Oscars last year where he won the Best Actor award for his portrayal of Stephen Hawking. It's a demanding performance, embodying Hawkins' motor neurone disease, but Redmayne maintains that the hardest part was fighting his fear of disappointing the real Hawkins and his ex-wife Jane.
Marion Cotillard as Edith Piaf in 'La Vie En Rose'
Young French actress Marion Cotillard was launched to international stardom when she won an Oscar for La Vie En Rose in which she played singer Edith Piaf. At just 32 years old, Cotillard was expected to portray Piaf's whole adult life, from her discovery at 20 until her death at 47. She handles the task remarkably.