Who played Jason Bourne in 'The Bourne Identity'?

Who played Amy Dunne in 'Gone Girl'? Who played Will Hunting in 'Good Will Hunting'? Who played Sean Maguire in 'Good Will Hunting'? In which film is Sean Maguire a character? Who played Mark Watney in 'The Martian'? In which film is Mark Watney a character? Who played John Keating in 'Dead Poets Society'? In which film is John Keating a character?