4. Gregory Peck - To Kill A Mockingbird (1962)
Although the bulk of my selections here might not reflect this, powerful performances need not be rooted primarily in despair. There is equal power in hope, even if that impulse sometimes proves elusive, or harder to present with the same credibility. However, Gregory Peck's performance as Atticus Finch is as powerful an embodiment of hope on film as we could ever wish for. Given that more than fifty years on, the racial tensions which underline Harper Lee's classic novel have by no means been completely resolved, To Kill A Mockingbird's core message is as potent today as it has ever been. As the decent man standing up for what is right in the face of widespread prejudice, Peck's Finch is an inspiring figure, and his summation in Tom Robinson's defence is stirring to say the least.