1. Christian Bale - The Machinist
Christian Bale lost over 60 pounds to portray an emaciated insomniac in this psychological thriller, shocking viewers with his skeletal appearance.
2. Charlize Theron - Monster
Charlize Theron gained 30 pounds, wore prosthetic teeth, and underwent extensive makeup to portray serial killer Aileen Wuornos, completely transforming her glamorous appearance.
3. Robert De Niro - Raging Bull
De Niro gained an astonishing 60 pounds to portray the older version of boxer Jake LaMotta, then went on a strict diet to lose the weight and convincingly portray the younger version.
4. Rooney Mara - The Girl with the Dragon Tattoo
Known for her delicate features, Mara underwent multiple body piercings and bleached her eyebrows to portray the fiercely intense Lisbeth Salander.
5. Jared Leto - Dallas Buyers Club
Leto lost 30 pounds and waxed his entire body to play a transgender woman with AIDS, showing immense dedication to the role.
6. Tom Hanks - Cast Away
Hanks gained 50 pounds for the beginning of the film and then lost it all to portray a marooned FedEx executive, showcasing the physical toll of being stranded on a deserted island.
7. Heath Ledger - The Dark Knight
Ledger's chilling portrayal of the Joker required him to immerse himself in the role, both mentally and physically, resulting in an unforgettable and haunting performance.
8. Natalie Portman - Black Swan
Portman trained for months, enduring intense ballet training and losing 20 pounds to accurately portray a ballerina descending into madness.
9. Matthew McConaughey - Dallas Buyers Club
McConaughey lost over 40 pounds to play an AIDS patient, showcasing his commitment to the role and earning him critical acclaim.
10. Johnny Depp - Pirates of the Caribbean
Depp's eccentric portrayal of Captain Jack Sparrow became iconic, with his quirky mannerisms and distinctive look captivating audiences worldwide.