10 Most Heartbreaking Doctor Who Moments
7. River In The Library
Time is a funny thing, we meet River and watch her die before we even know who she is. One of the few people who knows more than the Doctor, she reveals she is from his future.
In a heartbreaking speech she explains he must have always known how she died. She flirts with him, alluding to their future with a knowing wink in a style that becomes very familiar as we learn more and more about her. The Doctor asks how she knows his name to which she replies, "Spoilers" - her catchphrase, and also tragically the last word she ever utters to him.
She sacrifices herself for the entire library, saving the lives of thousands of people, including the Doctor's. River's true power comes from her identity and as we discover more and more about her, this scene becomes even more heartbreaking. But who is she? Spoilers...