Being the history buff that I am, it took me a few viewings of this film to get myself past all the historical inaccuracies and start to appreciate it as a work of fiction based on historical events. I put it in the same category as Gladiator, being that it's nice to look at but about as factual as Mary Poppins.
The plot revolves around two sisters, Mary and Anne, and how they were used by their father and uncle as instruments to improve the family standing in the court of Henry VIII. Knowing that Queen Catherine of Aragon can not provide the king with the son he so desires, the scheme is to toss either Mary or Anne into the King's bed in hopes that one or the other of them can fill that need of his.
Mary is portrayed as the sweeter and more innocent of the two, which seems odd that she is also the one who is very quick to hop into the royal bed. After she conceives and is shut away in a room to wait out the pregnancy, the more conniving Anne is sent to court in order to keep the King focused on Mary instead of chasing after some new maiden. Anne, bitter about her sister ratting her out about some of her misdeeds in order to protect the family reputation, lures the king away from her but holds off on jumping into bed with him until he's divorced his wife, spurned Mary and his newborn son, and crowned her as queen.
Henry soon grows tired of his marriage to Anne when she also fails to provide him with a son, and begins taking steps to get her out of his life. Permanently.
The main focus of the film is the love-hate relationship between the two sisters, but the story seems stray from this at times and drag on a bit slowly. Once Henry marries Anne, the pace picks up to break-neck speed and seems very rushed to get all the pertinent information out to explain how Anne ended up on the scaffold. This imbalance between the time before and after Anne's coronation seems to really throw off the overall flow of the story.
While the visuals are very pretty, the performances tend to fall a little flat on delivery. Some of the dialog seems to be a bit too proper and rehearsed, even for an English royal court. When Catherine of Aragon speaks, you can imagine her practicing every word in a mirror prior to her appearance. Anne's clever zingers often lose their zip, Mary's dialogue often sounds like a Harlequin novel, and the male characters seem to all be in the same Shakespeare study group.
However, with the slew of Tudor Period themed films that have been coming out lately, this is by no means the worst I've seen. It's certainly more of a chick flick than a history lesson, but worth a watch if English history is your cup of tea.
Info on IMDB: The Other Boleyn Girl