This movie stars Judi Dench and Cate Blanchett. The acting is the best I have ever seen with both of these stars giving really really good performances. In terms of the story line, it's about an average woman who decides to become a school teacher and becomes sexually involved with one of her students. Another teacher, whom she has befriended finds out about this and uses it to her advantage.
Judi Dench plays a great part here as the social parasite posing as a friend. The subject matter is definitely not for kids though, but explores adult themes of friendship and boundaries in our lives.