10. 'This Boy's Life' (1993)
This adaptation of Tobias Wolff's memoir gave DiCaprio one of his earliest leading roles: Toby, the loving son of troubled single mom Ellen Barkin. When she shacks up with a seemingly respectable but domineering and abusive Robert De Niro, it's war between the adolescent offspring and his stepfather-to-be. It's an evocative, touching little movie, defined by the powerful bond between Barkin and DiCaprio. And as the young actor's character goes from being a wide-eyed son to a rebellious greaser to an independent, sensitive young man, his performance gains complexity.