"The Woman in Gold" is probably Gustav Klimt's most famous painting (Wikipedia article with photo) and also possibly the most famous portrait ever painted. This movie is about the history of that painting, and its eventual restitution to the family decades after it was seized by the Nazis.
Helen Mirren (with brown contacts, which I found oddly disturbing) plays Maria Altmann, an Austrian Jew now living in Los Angeles. When she discovers after her sister's death that she might have rights to the Klimt portrait of her aunt that had hung in her family home for her entire childhood, she asks a friend whose son is a lawyer if she can borrow him for a bit ... The lawyer in question is E. Randol "Randy" Schoenberg (played by Ryan Reynolds), grandson of the famous composer and also of Austrian descent. He has no experience and little initial interest, but the case gets under his skin and he begins to pursue it.
The movie has far too many flashbacks, although I understand the need to put some of the information about the family, their history, and the painting before us. Mirren and Reynolds made a very compelling pair, but the young Maria (Tatiana Maslany) and her husband (Max Irons) in the flashbacks weren't as good. The movie was also overly sentimental and manipulative with some very heavy-handed music.
That said, Mirren and Reynolds were very good, and the story is fascinating - both the picture in history of a rich Viennese Jewish family, and the whole history of the picture's restitution.
If you watch the movie, it's worth your time to read the Historical Accuracy section of the Wikipedia article (not brutally bad, but they - typically of Hollywood - over-emphasized the American angle and made some other dubious changes).