* Jodie Foster won Best Actress for her roles as Iris and the younger Iris in "The Accused" (1988).
* Jamie Foxx won Best Actor for his roles as Ray Charles and his childhood self in "Ray" (2004).
* Daniel Day-Lewis won Best Actor for his roles as Christy Brown and his alter ego in "My Left Foot" (1989).
It's important to note that some actors may have played more than one role in a movie without necessarily having them be distinct "dual roles." For example, an actor might play multiple personalities within a single character. However, the cases listed above clearly involve separate characters, each played by the same actor.