Top 10 Hardest Acting Roles Played by Actors/Actresses

The Top Ten
1 Tom Hanks's Forrest Gump (Forrest Gump)
2 Heath Ledger's Joker (The Dark Knight)
3 Jack Nicholson's Jack Torrance (The Shining)

And he never got an oscar for it.

4 Dustin Hoffman's Raymond Babbitt (Rain Man)

its always important for an actor to play a mentally challenged role well out of respect. Sean Penn did it very well in "I Am Sam" and Dustin Hoffman also did in "Rain Man"

5 Marlon Brando's Vito Corleone (The Godfather)
6 Jack Nicholson's McMurphy (One Flew Over the Cuckoo's Nest)
7 James Gandolfini's Tony Soprano (The Sopranos)
8 Christian Bale's Trevor Reznik (The Machinist)
9 Mickey Rourke's Randy Robinson (The Wrestler)
10 Leonardo DiCaprio's Hugh Glass (The Revenant)
The Contenders
11 Meryl Streep's Margaret Thatche (The Iron Lady)
12 Robert Downey Jr.'s Iron Man/Tony Stark (Iron Man Series)
13 Tom Hardy's Bane (The Dark Knight Rises) Edward Thomas Hardy, CBE is an English actor and film producer. Originally a model, Hardy made his film debut in Ridley Scott’s Black Hawk Down.
14 Christoph Waltz's Col. Hans Landa (Inglorious Basterds)
15 Scarlett Johansson's Alien (Under the Skin)
16 Joaquin Phoenix's Joker/Arthur Fleck (Joker)
17 Robert Downey Jr.'s Kirk Lazarus (Tropic Thunder)
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