Because you like Colter Stevens in Source Code
R2-D2 has been in the galaxy saving business for decades. Not bad for somebody whose vocabulary is limited to "beep-boop." See them in Star Wars Series.
A bumbling hobbit, Bilbo Baggins is becoming a part of something much larger than himself as he embarks on a quest. See them in The Hobbit: An Unexpected Journey.
Running away from murderous aliens has turned into an interstellar chase for Jupiter Jones. See them in Jupiter Ascending.
Neil Perry is a brilliant student with an artist's soul. And he's desperate to unleash it. See them in Dead Poets Society.
Hans Landa doesn't seem to have issues with Jews, but he hunts them because he's determined to do his job well. See them in Inglourious Basterds.
Although Mako Mori may be small and quiet, she is a core of battle-hardened steel. See them in Pacific Rim.
A suave demon, Crowley grants humans their wishes in exchange for their soul, only to find loopholes that benefit him. See them in Supernatural.
There is never a dull moment with Jim Moriarty: expect booze and sing alongs in between all of the homicide. See them in Sherlock.
Toph is a tenacious earthbender full of spirit and spunk and hates when people try to baby her because she's blind. See them in Avatar: The Last Airbender.
Selfishly taking her father’s place to fight in the Imperial Army, Hua Mulan risks treason if they find out she isn’t who she says she is. See them in Mulan.