Agora (2009) starring Rachel Weisz as Hypatia.
Directed by Alejandro Amenabar, this film contains the best depiction of what it is like to do mathematics that I have seen in a movie. It's also beautifully filmed.
Spoiler alert! Stop reading now if you plan to see the movie.
The writers chose to (very likely!) bend facts by suggesting that Hypatia deduced that planets orbit in ellipses just before she was stoned to death. Her struggle, however, to solve this problem is given in vignettes stretching over a significant period of time culminating in a great Aha! moment.